activation. previously the timer would deactivate the screen
saver shortly after activation. job timer is restored when
the screen saver is deactivated.
installing and uninstalling the new error handler, causing
errors before the lock to be caught and errors during the lock
to not be caught. had to add Display* as argument to c'tor.
and untested. also some known problems: not detecting an
xscreensaver started after us and not detecting built-in
screen saver activation (not sure if we can without using
ugly extensions).
crs