Option "DontVTSwitch" "on" have no effect, it's same as "off". You can't disable the console switching. I have fix it with a hack in xc/programs/Xserver/hw/xfree86/os-support/linux/lnx_kbd.c.
Please tell me if you will see the patch to fix the problem.
Can you attach the patch you mentioned?
looks like it's fixed in head since long ago: http://cvs.freedesktop.org/xorg/xc/programs/Xserver/hw/xfree86/os-support/linux/lnx_kbd.c?r1=1.2&r2=1.3 so, closing
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