http://bugs.winehq.org/show_bug.cgi?id=22400
--- Comment #20 from Roderick Colenbrander thunderbird2k@gmail.com 2010-04-19 16:10:25 --- The black screen is a different issue and would require a different bug report. I can't easily say what the issue is but considering the quality of the radeon driver don't be surprised if it is a driver bug. Try disabling FBOs in the registry (OffscreenRenderingMode). I'll submit this patch.