I'm familiar with the problem you have described. When switching a VT, specific operation from an X client results in an X server crash, sometimes causing a kernel hang as well.
I say "specific" because icewm will rarely trigger this bug, a web page with animation on galeon will often do, and kde is a trigger as well. How much VideoRam did you allocate for the I810? I used to suffer from this problem when it was set to 16MB, however It went away when reducing VideoRam to 4MB -- Idan
