Hi,
Some time ago I did some tests of Wine on Solaris x86 and found that there is a problem with the way we handle threads due to the differences between the Linux and Solaris threading models. These differences are also relevant for Solaris Sparc and probably many other Unices.
Unfortunately I don't have time to work on it anymore so I created a bug report in Bugzilla where I tried to dump the relevant information, including a patch to illustrate the issues and the start of a fix. I hope it will be useful to someone... maybe Gregg who has been doing a lot of Solaris work recently.
http://bugs.winehq.com/show_bug.cgi?id=904