http://bugs.winehq.org/show_bug.cgi?id=11944
--- Comment #7 from Roderick Colenbrander thunderbird2k@gmx.net 2008-03-09 07:55:26 --- Why are you using a separate Xserver? I guess you are using XGL but plain Xorg + compiz should work fine too.
Second make sure that you explicitly set WINEDEBUG=+wgl,+x11drv,+synchronous as I'm not seeing any +x11drv traces. So set the variable using export.