http://bugs.winehq.org/show_bug.cgi?id=28086
--- Comment #3 from Nikolay Sivov bunglehead@gmail.com 2011-08-14 15:41:50 CDT --- I'm not sure how to test that. If I manually revert this commit on current tree I still can't get button work with mouse.
How does it look on Windows by the way? I mean when you press it with mouse click does it different bitmap indicating 'pressed' button state? My guess is that SetDIBits fails for some reason and some code path after repainting is skipped.