The ATI binary driver overwrites some cpu registers it should not touch by default. Although Wine attemts to catch this, the check seems to fail sometimes, resulting in a crash when initializing winex11.drv:
=>1 0xf7cf0d63 (0x0034e988)
2 0x7e90e7c7 in winex11 (+0x3e7c7) (0x0034ea08)
3 0x7e910b75 X11DRV_setup_opengl_visual+0x35() in winex11 (0x0034eaf8)
4 0x7e921738 in winex11 (+0x51738) (0x0034ed08)
A workaround is to set UseFastTLS to "2" in fglrx's driver section in xorg.conf:
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