It has been a while since I messed with such things, but I seem to recall something like that happening if I would load Xorg-7.5.tcz from a command line window while Xvesa (base) was still running. It seemed like exittc didn't know how to get out of the gui. I was using jwm, so probably not wm-specific if it is the same thing - I don't remember what version of tc/mc I was using but it was pre-3.5.1, don't know if it still does this or not. It would always behave as expected after a ctrl-alt-backspace (exit to prompt would work if I tried it again).