I think this is the link you need. Apparently MS knows the issue and this is their "workaround". It seems to force that first connection and the creation/filling the cached OST file.
http://support.microsoft.com/kb/913843
It worked for me (after a week of tearing out my hair), so good luck.
Paul
EggHeadCafe - .NET Developer Portal of Choice
http://www.eggheadcafe.com