I've a very strange problem. A user with a Blackberry 9700 has noticed issues with items not appearing in his calendar. After some investigation, it appears that if someone else sends a meeting request to him, and his PA accepts on his behalf, the meeting doesn't appear in his Blackberry calendar. It appears fine in the users Outlook calendar though. All other meetings appear to sync fine with the Blackberry.

Both user and PA are on Office 2010 since about November, after moving from Office 2003. I'm unsure if this issue arose immediately after this move, but I only heard about it afterwards.

Has anyone seen anything similar?

This sound like an Outlook issue. Just for a test, have the assistant accept the meeting on his PC if possible. I suspect the acceptance is not flowing to the BES server when accepted by an alternate. If this works then you can check to see if there is a delegate issue setting that needs to be checked on either the Outlook or BES.