diff --git a/client/CClient.cpp b/client/CClient.cpp
index c3d44cfd..3f8ec103 100644
--- a/client/CClient.cpp
+++ b/client/CClient.cpp
@@ -32,7 +32,8 @@ CClient::CClient(const CString& clientName) :
 								m_output(NULL),
 								m_screen(NULL),
 								m_active(false),
-								m_seqNum(0)
+								m_seqNum(0),
+								m_ignoreMove(false)
 {
 	// do nothing
 }
@@ -106,7 +107,7 @@ void					CClient::onClipboardChanged(ClipboardID id)
 	m_timeClipboard[id] = 0;
 
 	// if we're not the active screen then send the clipboard now,
-	// otherwise we'll until we leave.
+	// otherwise we'll wait until we leave.
 	if (!m_active) {
 		// get clipboard
 		CClipboard clipboard;
@@ -127,6 +128,19 @@ void					CClient::onClipboardChanged(ClipboardID id)
 	}
 }
 
+void					CClient::onResolutionChanged()
+{
+	log((CLOG_DEBUG "resolution changed"));
+
+	CLock lock(&m_mutex);
+
+	// start ignoring mouse movement until we get an acknowledgment
+	m_ignoreMove = true;
+
+	// send notification of resolution change
+	onQueryInfoNoLock();
+}
+
 #include "CTCPSocket.h" // FIXME
 void					CClient::runSession(void*)
 {
@@ -261,6 +275,9 @@ void					CClient::runSession(void*)
 			else if (memcmp(code, kMsgQInfo, 4) == 0) {
 				onQueryInfo();
 			}
+			else if (memcmp(code, kMsgCInfoAck, 4) == 0) {
+				onInfoAcknowledgment();
+			}
 			else if (memcmp(code, kMsgDClipboard, 4) == 0) {
 				onSetClipboard();
 			}
@@ -399,10 +416,13 @@ void					CClient::onLeave()
 				// marshall the data
 				CString data = clipboard.marshall();
 
-				// send data
-				log((CLOG_DEBUG "sending clipboard %d seqnum=%d, size=%d", id, m_seqNum, data.size()));
-				CProtocolUtil::writef(m_output,
+				// save and send data if different
+				if (data != m_dataClipboard[id]) {
+					log((CLOG_DEBUG "sending clipboard %d seqnum=%d, size=%d", id, m_seqNum, data.size()));
+					m_dataClipboard[id] = data;
+					CProtocolUtil::writef(m_output,
 								kMsgDClipboard, id, m_seqNum, &data);
+				}
 			}
 		}
 	}
@@ -441,13 +461,26 @@ void					CClient::onScreenSaver()
 
 void					CClient::onQueryInfo()
 {
-	SInt32 w, h;
+	CLock lock(&m_mutex);
+	onQueryInfoNoLock();
+}
+
+void					CClient::onQueryInfoNoLock()
+{
+	SInt32 x, y, w, h;
+	m_screen->getMousePos(&x, &y);
 	m_screen->getSize(&w, &h);
 	SInt32 zoneSize = m_screen->getJumpZoneSize();
 
-	log((CLOG_DEBUG1 "sending info size=%d,%d zone=%d", w, h, zoneSize));
+	log((CLOG_DEBUG1 "sending info size=%d,%d zone=%d pos=%d,%d", w, h, zoneSize, x, y));
+	CProtocolUtil::writef(m_output, kMsgDInfo, w, h, zoneSize, x, y);
+}
+
+void					CClient::onInfoAcknowledgment()
+{
+	log((CLOG_DEBUG1 "recv info acknowledgment"));
 	CLock lock(&m_mutex);
-	CProtocolUtil::writef(m_output, kMsgDInfo, w, h, zoneSize);
+	m_ignoreMove = false;
 }
 
 void					CClient::onSetClipboard()
@@ -536,13 +569,17 @@ void					CClient::onMouseUp()
 
 void					CClient::onMouseMove()
 {
+	bool ignore;
 	SInt16 x, y;
 	{
 		CLock lock(&m_mutex);
 		CProtocolUtil::readf(m_input, kMsgDMouseMove + 4, &x, &y);
+		ignore = m_ignoreMove;
 	}
 	log((CLOG_DEBUG2 "recv mouse move %d,%d", x, y));
-	m_screen->mouseMove(x, y);
+	if (!ignore) {
+		m_screen->mouseMove(x, y);
+	}
 }
 
 void					CClient::onMouseWheel()
diff --git a/client/CClient.h b/client/CClient.h
index 498a9d5b..a6c0cea1 100644
--- a/client/CClient.h
+++ b/client/CClient.h
@@ -23,6 +23,7 @@ public:
 
 	// handle events on client's screen
 	void				onClipboardChanged(ClipboardID);
+	void				onResolutionChanged();
 
 	// accessors
 
@@ -40,6 +41,8 @@ private:
 	void				onGrabClipboard();
 	void				onScreenSaver();
 	void				onQueryInfo();
+	void				onQueryInfoNoLock();
+	void				onInfoAcknowledgment();
 	void				onSetClipboard();
 	void				onKeyDown();
 	void				onKeyRepeat();
@@ -61,8 +64,10 @@ private:
 	const CNetworkAddress*	m_serverAddress;
 	bool				m_active;
 	UInt32				m_seqNum;
+	bool				m_ignoreMove;
 	bool				m_ownClipboard[kClipboardEnd];
 	IClipboard::Time	m_timeClipboard[kClipboardEnd];
+	CString				m_dataClipboard[kClipboardEnd];
 };
 
 #endif
diff --git a/client/CMSWindowsSecondaryScreen.cpp b/client/CMSWindowsSecondaryScreen.cpp
index cdca03c4..26a97fa5 100644
--- a/client/CMSWindowsSecondaryScreen.cpp
+++ b/client/CMSWindowsSecondaryScreen.cpp
@@ -315,6 +315,23 @@ void					CMSWindowsSecondaryScreen::grabClipboard(ClipboardID id)
 	}
 }
 
+void					CMSWindowsSecondaryScreen::getMousePos(
+								SInt32* x, SInt32* y) const
+{
+	assert(x != NULL);
+	assert(y != NULL);
+
+	POINT pos;
+	if (GetCursorPos(&pos)) {
+		*x = pos.x;
+		*y = pos.y;
+	}
+	else {
+		*x = 0;
+		*y = 0;
+	}
+}
+
 void					CMSWindowsSecondaryScreen::getSize(
 								SInt32* width, SInt32* height) const
 {
@@ -420,6 +437,12 @@ LRESULT					CMSWindowsSecondaryScreen::onEvent(
 		else
 			SendMessage(m_nextClipboardWindow, msg, wParam, lParam);
 		return 0;
+
+	case WM_DISPLAYCHANGE:
+		// screen resolution has changed
+		updateScreenSize();
+		m_client->onResolutionChanged();
+		return 0;
 	}
 
 	return DefWindowProc(hwnd, msg, wParam, lParam);
diff --git a/client/CMSWindowsSecondaryScreen.h b/client/CMSWindowsSecondaryScreen.h
index 8149ea92..3ca03338 100644
--- a/client/CMSWindowsSecondaryScreen.h
+++ b/client/CMSWindowsSecondaryScreen.h
@@ -28,6 +28,7 @@ public:
 	virtual void		mouseWheel(SInt32 delta);
 	virtual void		setClipboard(ClipboardID, const IClipboard*);
 	virtual void		grabClipboard(ClipboardID);
+	virtual void		getMousePos(SInt32* x, SInt32* y) const;
 	virtual void		getSize(SInt32* width, SInt32* height) const;
 	virtual SInt32		getJumpZoneSize() const;
 	virtual void		getClipboard(ClipboardID, IClipboard*) const;
diff --git a/client/CXWindowsSecondaryScreen.cpp b/client/CXWindowsSecondaryScreen.cpp
index 010c4475..1a58a7bd 100644
--- a/client/CXWindowsSecondaryScreen.cpp
+++ b/client/CXWindowsSecondaryScreen.cpp
@@ -323,6 +323,19 @@ void					CXWindowsSecondaryScreen::grabClipboard(ClipboardID id)
 	setDisplayClipboard(id, NULL, m_window, getCurrentTime(m_window));
 }
 
+void					CXWindowsSecondaryScreen::getMousePos(
+								SInt32* x, SInt32* y) const
+{
+	CDisplayLock display(this);
+	int xTmp, yTmp, dummy;
+	unsigned int dummyMask;
+	Window dummyWindow;
+	XQueryPointer(display, getRoot(), &dummyWindow, &dummyWindow,
+								&xTmp, &yTmp, &dummy, &dummy, &dummyMask);
+	*x = xTmp;
+	*y = yTmp;
+}
+
 void					CXWindowsSecondaryScreen::getSize(
 								SInt32* width, SInt32* height) const
 {
diff --git a/client/CXWindowsSecondaryScreen.h b/client/CXWindowsSecondaryScreen.h
index 6aa1cb8b..44f63182 100644
--- a/client/CXWindowsSecondaryScreen.h
+++ b/client/CXWindowsSecondaryScreen.h
@@ -27,6 +27,7 @@ public:
 	virtual void		mouseWheel(SInt32 delta);
 	virtual void		setClipboard(ClipboardID, const IClipboard*);
 	virtual void		grabClipboard(ClipboardID);
+	virtual void		getMousePos(SInt32* x, SInt32* y) const;
 	virtual void		getSize(SInt32* width, SInt32* height) const;
 	virtual SInt32		getJumpZoneSize() const;
 	virtual void		getClipboard(ClipboardID, IClipboard*) const;
diff --git a/server/CMSWindowsPrimaryScreen.cpp b/server/CMSWindowsPrimaryScreen.cpp
index 546536d0..fa6d7e5c 100644
--- a/server/CMSWindowsPrimaryScreen.cpp
+++ b/server/CMSWindowsPrimaryScreen.cpp
@@ -61,6 +61,11 @@ void					CMSWindowsPrimaryScreen::open(CServer* server)
 	// get keyboard state
 	updateKeys();
 
+	// send screen info
+	SInt32 w, h;
+	getScreenSize(&w, &h);
+	m_server->setInfo(w, h, getJumpZoneSize(), 0, 0);
+
 	// enter the screen
 	doEnter();
 }
@@ -246,18 +251,35 @@ void					CMSWindowsPrimaryScreen::getClipboard(
 KeyModifierMask			CMSWindowsPrimaryScreen::getToggleMask() const
 {
 	KeyModifierMask mask = 0;
-	if ((m_keys[VK_CAPITAL] & 0x01) != 0)
+	if ((GetKeyState(VK_CAPITAL) & 0x01) != 0)
 		mask |= KeyModifierCapsLock;
-	if ((m_keys[VK_NUMLOCK] & 0x01) != 0)
+	if ((GetKeyState(VK_NUMLOCK) & 0x01) != 0)
 		mask |= KeyModifierNumLock;
-	if ((m_keys[VK_SCROLL] & 0x01) != 0)
+	if ((GetKeyState(VK_SCROLL) & 0x01) != 0)
 		mask |= KeyModifierScrollLock;
 	return mask;
 }
 
 bool					CMSWindowsPrimaryScreen::isLockedToScreen() const
 {
-	// FIXME
+	// check buttons
+	if (GetAsyncKeyState(VK_LBUTTON) < 0 ||
+		GetAsyncKeyState(VK_MBUTTON) < 0 ||
+		GetAsyncKeyState(VK_RBUTTON) < 0) {
+		return true;
+	}
+
+	// check keys
+	BYTE keys[256];
+	if (GetKeyboardState(keys)) {
+		for (unsigned int i = 0; i < sizeof(keys); ++i) {
+			if ((keys[i] & 0x80) != 0) {
+				return true;
+			}
+		}
+	}
+
+	// not locked
 	return false;
 }
 
@@ -433,13 +455,17 @@ bool					CMSWindowsPrimaryScreen::onPreTranslate(MSG* msg)
 				// get mouse deltas
 				x -= m_xCenter;
 				y -= m_yCenter;
-				log((CLOG_DEBUG2 "event: active move %d,%d", x, y));
 
-				// warp mouse back to center
-				warpCursor(m_xCenter, m_yCenter);
+				// ignore if the mouse didn't move
+				if (x != 0 && y != 0) {
+					log((CLOG_DEBUG2 "event: active move %d,%d", x, y));
 
-				// send motion
-				m_server->onMouseMoveSecondary(x, y);
+					// warp mouse back to center
+					warpCursor(m_xCenter, m_yCenter);
+
+					// send motion
+					m_server->onMouseMoveSecondary(x, y);
+				}
 			}
 		}
 		return true;
@@ -485,6 +511,36 @@ LRESULT					CMSWindowsPrimaryScreen::onEvent(
 		else
 			SendMessage(m_nextClipboardWindow, msg, wParam, lParam);
 		return 0;
+
+	case WM_DISPLAYCHANGE: {
+		// screen resolution has changed
+		SInt32 w, h;
+		updateScreenSize();
+		getScreenSize(&w, &h);
+
+		// recompute center pixel of screen
+		m_xCenter = w >> 1;
+		m_yCenter = h >> 1;
+
+		// warp mouse to center if active
+		if (m_active) {
+			warpCursor(m_xCenter, m_yCenter);
+		}
+
+		// tell hook about resize if not active
+		else {
+			SetZoneFunc setZone = (SetZoneFunc)GetProcAddress(
+											m_hookLibrary, "setZone");
+			setZone(m_server->getActivePrimarySides(), w, h, getJumpZoneSize());
+		}
+
+		// send new screen info
+		POINT pos;
+		GetCursorPos(&pos);
+		m_server->setInfo(w, h, getJumpZoneSize(), pos.x, pos.y);
+
+		return 0;
+	}
 	}
 
 	return DefWindowProc(hwnd, msg, wParam, lParam);
diff --git a/server/CServer.cpp b/server/CServer.cpp
index 09739198..6c8001a3 100644
--- a/server/CServer.cpp
+++ b/server/CServer.cpp
@@ -132,8 +132,16 @@ UInt32					CServer::getActivePrimarySides() const
 	return sides;
 }
 
+void					CServer::setInfo(
+								SInt32 w, SInt32 h, SInt32 zoneSize,
+								SInt32 x, SInt32 y)
+{
+	setInfo(m_primaryInfo->m_name, w, h, zoneSize, x, y);
+}
+
 void					CServer::setInfo(const CString& client,
-								SInt32 w, SInt32 h, SInt32 zoneSize)
+								SInt32 w, SInt32 h, SInt32 zoneSize,
+								SInt32 x, SInt32 y)
 {
 	assert(!client.empty());
 	assert(w > 0);
@@ -151,12 +159,29 @@ void					CServer::setInfo(const CString& client,
 	// update client info
 	CScreenInfo* info = index->second;
 	if (info == m_active) {
-		// FIXME -- ensure mouse is still on screen.  warp it if necessary.
+		// update the remote mouse coordinates
+		m_x = x;
+		m_y = y;
 	}
 	info->m_width    = w;
 	info->m_height   = h;
 	info->m_zoneSize = zoneSize;
-	log((CLOG_NOTE "client \"%s\" size=%dx%d zone=%d", client.c_str(), w, h, zoneSize));
+	log((CLOG_NOTE "client \"%s\" size=%dx%d zone=%d pos=%d,%d", client.c_str(), w, h, zoneSize, x, y));
+
+	// send acknowledgement (if client isn't the primary)
+	if (info->m_protocol != NULL) {
+		info->m_protocol->sendInfoAcknowledgment();
+	}
+
+	// handle resolution change to primary screen
+	else {
+		if (info == m_active) {
+			onMouseMovePrimary(x, y);
+		}
+		else {
+			onMouseMoveSecondary(0, 0);
+		}
+	}
 }
 
 void					CServer::grabClipboard(ClipboardID id)
@@ -1011,6 +1036,10 @@ void					CServer::openPrimaryScreen()
 	// reset sequence number
 	m_seqNum = 0;
 
+	// add connection
+	m_active = addConnection(CString("primary"/* FIXME */), NULL);
+	m_primaryInfo = m_active;
+
 	// open screen
 	log((CLOG_DEBUG1 "creating primary screen"));
 #if defined(CONFIG_PLATFORM_WIN32)
@@ -1021,16 +1050,6 @@ void					CServer::openPrimaryScreen()
 	log((CLOG_DEBUG1 "opening primary screen"));
 	m_primary->open(this);
 
-	// add connection
-	m_active = addConnection(CString("primary"/* FIXME */), NULL);
-	m_primaryInfo = m_active;
-
-	// update info
-	m_primary->getSize(&m_active->m_width, &m_active->m_height);
-	m_active->m_zoneSize = m_primary->getJumpZoneSize();
-	log((CLOG_NOTE "server size=%dx%d zone=%d", m_active->m_width, m_active->m_height, m_active->m_zoneSize));
-	// FIXME -- need way for primary screen to call us back
-
 	// set the clipboard owner to the primary screen and then get the
 	// current clipboard data.
 	for (ClipboardID id = 0; id < kClipboardEnd; ++id) {
diff --git a/server/CServer.h b/server/CServer.h
index 321017ce..5cdadfe5 100644
--- a/server/CServer.h
+++ b/server/CServer.h
@@ -46,9 +46,16 @@ public:
 	void				onMouseWheel(SInt32 delta);
 	void				grabClipboard(ClipboardID);
 
+	// handle updates from primary
+	void				setInfo(SInt32 wScreen, SInt32 hScreen,
+								SInt32 zoneSize,
+								SInt32 xMouse, SInt32 yMouse);
+
 	// handle messages from clients
 	void				setInfo(const CString& clientName,
-								SInt32 w, SInt32 h, SInt32 zoneSize);
+								SInt32 wScreen, SInt32 hScreen,
+								SInt32 zoneSize,
+								SInt32 xMouse, SInt32 yMouse);
 	void				grabClipboard(ClipboardID,
 								UInt32 seqNum, const CString& clientName);
 	void				setClipboard(ClipboardID,
@@ -187,6 +194,7 @@ private:
 	// the sequence number of enter messages
 	UInt32				m_seqNum;
 
+	// current mouse position (in absolute secondary screen coordinates)
 	SInt32				m_x, m_y;
 
 	CScreenMap			m_screenMap;
diff --git a/server/CServerProtocol.h b/server/CServerProtocol.h
index c64fa6cf..47ae856d 100644
--- a/server/CServerProtocol.h
+++ b/server/CServerProtocol.h
@@ -37,6 +37,7 @@ public:
 	virtual void		sendClipboard(ClipboardID, const CString&) = 0;
 	virtual void		sendGrabClipboard(ClipboardID) = 0;
 	virtual void		sendScreenSaver(bool on) = 0;
+	virtual void		sendInfoAcknowledgment() = 0;
 	virtual void		sendKeyDown(KeyID, KeyModifierMask) = 0;
 	virtual void		sendKeyRepeat(KeyID, KeyModifierMask, SInt32 count) = 0;
 	virtual void		sendKeyUp(KeyID, KeyModifierMask) = 0;
diff --git a/server/CServerProtocol1_0.cpp b/server/CServerProtocol1_0.cpp
index e9ed0519..1d4240f0 100644
--- a/server/CServerProtocol1_0.cpp
+++ b/server/CServerProtocol1_0.cpp
@@ -124,6 +124,12 @@ void					CServerProtocol1_0::sendScreenSaver(bool on)
 	CProtocolUtil::writef(getOutputStream(), kMsgCScreenSaver, on ? 1 : 0);
 }
 
+void					CServerProtocol1_0::sendInfoAcknowledgment()
+{
+	log((CLOG_DEBUG1 "send info ack to \"%s\"", getClient().c_str()));
+	CProtocolUtil::writef(getOutputStream(), kMsgCInfoAck);
+}
+
 void					CServerProtocol1_0::sendKeyDown(
 								KeyID key, KeyModifierMask mask)
 {
@@ -176,17 +182,21 @@ void					CServerProtocol1_0::sendMouseWheel(
 void					CServerProtocol1_0::recvInfo()
 {
 	// parse the message
-	SInt16 w, h, zoneInfo;
-	CProtocolUtil::readf(getInputStream(), kMsgDInfo + 4, &w, &h, &zoneInfo);
-	log((CLOG_DEBUG "received client \"%s\" info size=%dx%d, zone=%d", getClient().c_str(), w, h, zoneInfo));
+	SInt16 x, y, w, h, zoneInfo;
+	CProtocolUtil::readf(getInputStream(), kMsgDInfo + 4,
+								&w, &h, &zoneInfo, &x, &y);
+	log((CLOG_DEBUG "received client \"%s\" info size=%dx%d, zone=%d, pos=%d,%d", getClient().c_str(), w, h, zoneInfo, x, y));
 
 	// validate
 	if (w <= 0 || h <= 0 || zoneInfo < 0) {
 		throw XBadClient();
 	}
+	if (x < 0 || y < 0 || x >= w || y >= h) {
+		throw XBadClient();
+	}
 
 	// tell server of change
-	getServer()->setInfo(getClient(), w, h, zoneInfo);
+	getServer()->setInfo(getClient(), w, h, zoneInfo, x, y);
 }
 
 void					CServerProtocol1_0::recvClipboard()
diff --git a/server/CServerProtocol1_0.h b/server/CServerProtocol1_0.h
index e7fbcc58..4114643e 100644
--- a/server/CServerProtocol1_0.h
+++ b/server/CServerProtocol1_0.h
@@ -22,6 +22,7 @@ public:
 	virtual void		sendClipboard(ClipboardID, const CString&);
 	virtual void		sendGrabClipboard(ClipboardID);
 	virtual void		sendScreenSaver(bool on);
+	virtual void		sendInfoAcknowledgment();
 	virtual void		sendKeyDown(KeyID, KeyModifierMask);
 	virtual void		sendKeyRepeat(KeyID, KeyModifierMask, SInt32 count);
 	virtual void		sendKeyUp(KeyID, KeyModifierMask);
diff --git a/server/CXWindowsPrimaryScreen.cpp b/server/CXWindowsPrimaryScreen.cpp
index 26e374c0..db112338 100644
--- a/server/CXWindowsPrimaryScreen.cpp
+++ b/server/CXWindowsPrimaryScreen.cpp
@@ -268,6 +268,11 @@ void					CXWindowsPrimaryScreen::open(CServer* server)
 		CDisplayLock display(this);
 		updateModifierMap(display);
 	}
+
+	// send screen info
+	SInt32 w, h;
+	getScreenSize(&w, &h);
+	m_server->setInfo(w, h, getJumpZoneSize(), 0, 0);
 }
 
 void					CXWindowsPrimaryScreen::close()
diff --git a/synergy/CMSWindowsScreen.cpp b/synergy/CMSWindowsScreen.cpp
index 49860496..ff2c2e39 100644
--- a/synergy/CMSWindowsScreen.cpp
+++ b/synergy/CMSWindowsScreen.cpp
@@ -135,6 +135,13 @@ ATOM					CMSWindowsScreen::getClass() const
 	return m_class;
 }
 
+void					CMSWindowsScreen::updateScreenSize()
+{
+	m_w = GetSystemMetrics(SM_CXSCREEN);
+	m_h = GetSystemMetrics(SM_CYSCREEN);
+	log((CLOG_INFO "display resize: %dx%d", m_w, m_h));
+}
+
 void					CMSWindowsScreen::getScreenSize(
 								SInt32* w, SInt32* h) const
 {
diff --git a/synergy/CMSWindowsScreen.h b/synergy/CMSWindowsScreen.h
index a916beb3..510ed3c6 100644
--- a/synergy/CMSWindowsScreen.h
+++ b/synergy/CMSWindowsScreen.h
@@ -40,6 +40,9 @@ protected:
 	static HINSTANCE	getInstance();
 	ATOM				getClass() const;
 
+	// update screen size cache
+	void				updateScreenSize();
+
 	// get the size of the screen
 	void				getScreenSize(SInt32* w, SInt32* h) const;
 
diff --git a/synergy/IPrimaryScreen.h b/synergy/IPrimaryScreen.h
index 02535ac9..4390addc 100644
--- a/synergy/IPrimaryScreen.h
+++ b/synergy/IPrimaryScreen.h
@@ -28,7 +28,11 @@ public:
 	// can't be detected then this object should disable the system's
 	// screen saver timer and should start the screen saver after
 	// idling for an appropriate time.
-	virtual void		open(CServer*) = 0;
+	//
+	// open() must call server->setInfo() to notify the server of the
+	// primary screen's resolution and jump zone size.  the mouse
+	// position is ignored and may be 0,0.
+	virtual void		open(CServer* server) = 0;
 
 	// close the screen.  should restore the screen saver timer if it
 	// was disabled.
diff --git a/synergy/ISecondaryScreen.h b/synergy/ISecondaryScreen.h
index c7f1ba3a..c5bd736e 100644
--- a/synergy/ISecondaryScreen.h
+++ b/synergy/ISecondaryScreen.h
@@ -66,6 +66,9 @@ public:
 
 	// accessors
 
+	// get the position of the mouse on the screen
+	virtual void		getMousePos(SInt32* x, SInt32* y) const = 0;
+
 	// get the size of the screen
 	virtual void		getSize(SInt32* width, SInt32* height) const = 0;
 
diff --git a/synergy/IServerProtocol.h b/synergy/IServerProtocol.h
index c8d40f2a..ecddeeda 100644
--- a/synergy/IServerProtocol.h
+++ b/synergy/IServerProtocol.h
@@ -30,6 +30,7 @@ public:
 	virtual void		sendClipboard(ClipboardID, const CString&) = 0;
 	virtual void		sendGrabClipboard(ClipboardID) = 0;
 	virtual void		sendScreenSaver(bool on) = 0;
+	virtual void		sendInfoAcknowledgment() = 0;
 	virtual void		sendKeyDown(KeyID, KeyModifierMask) = 0;
 	virtual void		sendKeyRepeat(KeyID, KeyModifierMask, SInt32 count) = 0;
 	virtual void		sendKeyUp(KeyID, KeyModifierMask) = 0;
diff --git a/synergy/ProtocolTypes.h b/synergy/ProtocolTypes.h
index 66b45c93..c8194961 100644
--- a/synergy/ProtocolTypes.h
+++ b/synergy/ProtocolTypes.h
@@ -50,6 +50,12 @@ static const char		kMsgCClipboard[] 	= "CCLP%1i%4i";
 // screensaver on primary has started ($1 == 1) or closed ($1 == 0)
 static const char		kMsgCScreenSaver[] 	= "CSEC%1i";
 
+// resolution change acknowledgment:  primary -> secondary
+// sent by primary in response to a secondary screen's kMsgDInfo.
+// this is sent for every kMsgDInfo, whether or not the primary
+// had sent a kMsgQInfo.
+static const char		kMsgCInfoAck[] = "CIAK";
+
 
 //
 // data codes
@@ -80,7 +86,8 @@ static const char		kMsgDMouseUp[]		= "DMUP%1i";
 static const char		kMsgDMouseMove[]	= "DMMV%2i%2i";
 
 // mouse button pressed:  primary -> secondary
-// $1 = delta
+// $1 = delta.  the delta should be +120 for one tick forward (away
+// from the user) and -120 for one tick backward (toward the user).
 static const char		kMsgDMouseWheel[]	= "DMWM%2i";
 
 // clipboard data:  primary <-> secondary
@@ -92,8 +99,16 @@ static const char		kMsgDClipboard[]	= "DCLP%1i%4i%s";
 
 // client data:  secondary -> primary
 // $1 = seconary screen width in pixels, $2 = screen height, $3 =
-// size of warp zone.
-static const char		kMsgDInfo[]			= "DINF%2i%2i%2i";
+// size of warp zone.  $4 and $5 are the x,y position of the mouse
+// on the secondary screen.
+//
+// the secondary screen must send this message in response to the
+// kMsgQInfo message.  it must also send this message when the
+// screen's resolution changes.  in this case, the secondary screen
+// should ignore any kMsgDMouseMove messages until it receives a
+// kMsgCInfoAck in order to prevent attempts to move the mouse off
+// the new screen area.
+static const char		kMsgDInfo[]			= "DINF%2i%2i%2i%2i%2i";
 
 
 //