http://bugs.winehq.org/show_bug.cgi?id=23453
--- Comment #8 from Vladimir Panteleev thecybershadow@gmail.com 2010-09-14 04:40:12 CDT --- Actually, if you look at the IsDialogMessage implementation, it's quite clear what's going on:
http://source.winehq.org/source/dlls/user32/dialog.c#L1224
DM_GETDEFID returns IDOK, but since there's no IDOK control on the dialog, Wine decides to not do anything (instead of sending the IDOK like on line 1231).
I suppose I'll prepare a patch and testcase for the test suite.