http://bugs.winehq.org/show_bug.cgi?id=16311
--- Comment #27 from Adys adys.wh+winehqdotorg@gmail.com 2009-01-11 08:20:48 --- We had a talk on IRC recently. I sent a new email, but should have precised here too. This issue only happens with Xinerama enabled.
Still unsure if this is a bug in Wine aswell, though.