Unless I'm misremembering, VMWare has never supported OS/2 as a client (or server for that matter). They heard from me during the early betas about that, but other than saying they were looking into it, AFAIK, they've never supported OS/2. I don't know if anyone has posted any pointers on any issues with it. I had always assumed that there weren't technical reasons for lack of support, but due to marketshare/cost of support/etc. issues - I don't know if there were Ring issues or not.
Parallels claims to support OS/2 and eCS clients. That's probably the safest route if you want OS/2 support - but "support" may have different meanings for them. Check out the [link|http://forum.parallels.com/showthread.php?t=13596&highlight=OS/2|forums] for some examples of issues. Spiceware has some tips there.
HTH a bit.
Cheers,
Scott.