http://bugs.winehq.org/show_bug.cgi?id=19412
--- Comment #15 from Charles Davis cdavis@mines.edu 2009-07-28 17:35:48 --- I seem to have better luck with GL_APPLE_client_storage than with GL_ARB_pixel_buffer_object. (With PBOs, for some reason, I get stack overflow exceptions somewhere in the heap manager. I know I get them in the heap manager because it takes the exception while holding the heap critical section, so when another thread tries to allocate memory, that thread blocks. But that's another bug, for another day.)
So, my recommendation is to disable PBOs where GL_APPLE_client_storage is supported (e.g. Mac OS) until you can come up with a proper fix.