Just a few weeks ago I’ve started using OpenFire (on windows 2008 x64 server) and Spark. Openfire is using AD, and it works with no problem.
Funny thing is that I can use SSO in spark only on Windows XP machines (all x86, not much left now - under 10%) on Vista and Windows 7 (all x64) it does not won’t too authenticate.
Any ideas? Where Should I look?