Problem solved by restoring original X start file.

maemo-pc-connectivity overwrites file "/etc/init.d/x-server" with additional X options. Replacing it with original file solves problem.

Working file contains following options line:
ARGS="-mouse tslib -nozap -dpi $DISPLAY_DPI -wr -nolisten tcp"

Broken file options are:

ARGS="-mouse tslib -nozap -dpi $DISPLAY_DPI -wr -nolisten tcp -extension XInputExtension"