diff --git a/Make-linux b/Make-linux
index 98572f46..8300b12d 100644
--- a/Make-linux
+++ b/Make-linux
@@ -13,7 +13,7 @@ RMR       = /bin/rm -rf
 #
 # compiler options
 #
-GCXXDEFS  = -D_XOPEN_SOURCE=600
+GCXXDEFS  = -D_XOPEN_SOURCE=600 -D_SVID_SOURCE
 GCXXINCS  = -I$(DEPTH)/include -I/usr/X11R6/include
 GCXXOPTS  = -Wall -W -fexceptions
 CXXOPTIMIZER = -g
diff --git a/net/CNetwork.h b/net/CNetwork.h
index fcc65e40..8d6e9842 100644
--- a/net/CNetwork.h
+++ b/net/CNetwork.h
@@ -9,6 +9,9 @@
 # define INCL_WINSOCK_API_TYPEDEFS 0
 # include <winsock2.h>
 typedef int ssize_t;
+# if !defined(SOL_TCP)
+#  define SOL_TCP IPPROTO_TCP
+# endif
 #else
 # define FAR
 # define PASCAL
@@ -21,6 +24,9 @@ typedef int ssize_t;
 # include <netdb.h>
 # include <netinet/in.h>
 # include <errno.h>
+# if !defined(TCP_NODELAY) || !defined(SOL_TCP)
+#  include <netinet/tcp.h>
+# endif
 #endif
 
 // FIXME -- must handle htonl and ilk when defined as macros
@@ -31,6 +37,7 @@ public:
 	typedef SOCKET Socket;
 	typedef struct sockaddr Address;
 	typedef int AddressLength;
+	typedef BOOL TCPNoDelayType;
 	struct PollEntry {
 		Socket			fd;
 		short			events;
@@ -47,6 +54,7 @@ public:
 	typedef struct sockaddr Address;
 	typedef socklen_t AddressLength;
 	typedef struct pollfd PollEntry;
+	typedef int TCPNoDelayType;
 	enum {
 		kPOLLIN = POLLIN,
 		kPOLLOUT = POLLOUT,
diff --git a/net/CTCPSocket.cpp b/net/CTCPSocket.cpp
index ce32c846..f5f4f3a5 100644
--- a/net/CTCPSocket.cpp
+++ b/net/CTCPSocket.cpp
@@ -128,6 +128,16 @@ void					CTCPSocket::init()
 	m_output    = new CBufferedOutputStream(m_mutex,
 								new TMethodJob<CTCPSocket>(
 									this, &CTCPSocket::closeOutput));
+
+	// turn off Nagle algorithm.  we send lots of very short messages
+	// that should be sent without (much) delay.  for example, the
+	// mouse motion messages are much less useful if they're delayed.
+	CNetwork::TCPNoDelayType flag = 1;
+	CNetwork::setsockopt(m_fd, SOL_TCP, TCP_NODELAY, &flag, sizeof(flag));
+
+	// don't buffer sends, we merge messages ourself
+	int data = 0;
+	CNetwork::setsockopt(m_fd, SOL_SOCKET, SO_SNDBUF, &data, sizeof(data));
 }
 
 void					CTCPSocket::ioThread(void*)
diff --git a/synergy/CXWindowsScreen.cpp b/synergy/CXWindowsScreen.cpp
index b3dd2bf2..58fb5d0a 100644
--- a/synergy/CXWindowsScreen.cpp
+++ b/synergy/CXWindowsScreen.cpp
@@ -261,6 +261,23 @@ void					CXWindowsScreen::getDisplayClipboard(
 	CLock lock(&m_mutex);
 	Atom selection = m_atomClipboard[id];
 
+	// if we're trying to request the clipboard from the same
+	// unresponsive owner then immediately give up.  this is lame
+	// because we can't be sure the owner won't become responsive;
+	// we can only ask the X server for the current owner, not the
+	// owner at time timestamp, allowing a race condition;  and we
+	// don't detect if the owner window is destroyed in order to
+	// reset the unresponsive flag.
+	Window owner = XGetSelectionOwner(m_display, selection);
+	if (m_clipboards[id].m_unresponsive) {
+		if (owner != None && owner == m_clipboards[id].m_owner) {
+			clipboard->close();
+			return;
+		}
+	}
+	CClipboardInfo& clipboardInfo =
+								const_cast<CClipboardInfo&>(m_clipboards[id]);
+
 	// ask the selection for all the formats it has.  some owners return
 	// the TARGETS atom and some the ATOM atom when TARGETS is requested.
 	Atom format;
@@ -268,6 +285,10 @@ void					CXWindowsScreen::getDisplayClipboard(
 	if (getDisplayClipboard(selection, m_atomTargets,
 								requestor, timestamp, &format, &targets) &&
 		(format == m_atomTargets || format == XA_ATOM)) {
+		// save owner info
+		clipboardInfo.m_owner        = owner;
+		clipboardInfo.m_unresponsive = false;
+
 		// get each target (that we can interpret).  some owners return
 		// some targets multiple times in the list so don't try to get
 		// those multiple times.
@@ -330,6 +351,11 @@ void					CXWindowsScreen::getDisplayClipboard(
 	else {
 		// non-ICCCM conforming selection owner.  try TEXT format.
 		// FIXME
+
+		// save owner info
+		clipboardInfo.m_owner        = owner;
+		clipboardInfo.m_unresponsive = true;
+
 		log((CLOG_DEBUG1 "selection doesn't support TARGETS, format is %d", format));
 	}
 
@@ -1014,7 +1040,9 @@ Time					CXWindowsScreen::getCurrentTimeNoLock(
 CXWindowsScreen::CClipboardInfo::CClipboardInfo() :
 								m_clipboard(),
 								m_lostClipboard(CurrentTime),
-								m_requests()
+								m_requests(),
+								m_owner(None),
+								m_unresponsive(false)
 {
 	// do nothing
 }
diff --git a/synergy/CXWindowsScreen.h b/synergy/CXWindowsScreen.h
index 66df2968..0f81414a 100644
--- a/synergy/CXWindowsScreen.h
+++ b/synergy/CXWindowsScreen.h
@@ -161,6 +161,12 @@ private:
 
 		// the request queues
 		CRequestMap		m_requests;
+
+		// owner of clipboard when we last asked for it
+		Window			m_owner;
+
+		// true iff the previous request to m_owner got no reply
+		bool			m_unresponsive;
 	};
 
 	Display*			m_display;