http://bugs.winehq.org/show_bug.cgi?id=20380
--- Comment #18 from Roderick Colenbrander thunderbird2k@gmail.com 2009-10-19 12:03:43 --- So the crash is over in latest GIT for you? If possible could you try a different display driver? E.g. catalyst 9.3 which still supports your card OR perhaps 'exa' can be disabled so that you use software xrender. I fear that the issue you are seeing now is a driver bug. Can some people using the nvidia drivers try as well? Their XRender implementation is quite decent.
Roderick