http://bugs.winehq.org/show_bug.cgi?id=22356
--- Comment #23 from Roderick Colenbrander thunderbird2k@gmail.com 2010-05-10 14:28:49 --- Perhaps I should have updated the comment when I resubmitted it. Apparently the bug you are seeing is slightly different and this patch only addresses one class of the issues (the patch is good).
I'm still not sure what the other issue is. As I mentioned last time, try what happens if surface_prepare_texture is called at the start of LoadLocation.