Tough Calendar problem

Hello folks. This is a Windows XP machine running Office 2003 all patched up
on an office network pointing to an Exchange 2003 server. I have a secretary
who has publishing editor rights to her managers calendar. The delegation is
setup so that meeting requests sent to the manager go directly to the
secretary's inbox and not to the manager. When the secretary reads the
meeting request the calendar appointment automatically shows up on her
managers calendar instantly whether she has accepted it or not. That is how
it is supposed to work. However, sometimes, (no rhyme or reason) when
receiving meeting requests from various individuals within the organization
the meeting request does not show up on the managers calendar. And when she
opens the meeting request in her inbox there is a message below the
accept/decline toolbar that says "this meeting is not in managers name
calendar". The weird part about this is that sometimes the meeting requests
go to the calendar fine and sometimes they don't even when they are sent from
the same individual. Again, this happens with various individuals who send
the request. I have recreated the secretary's Outlook profile, I have ran
detect and repair and I followed what appeared to be instructions to remove
every trace of Office 2003 (with a lot of registry keys to delete) but when I
reinstalled Outlook it still remembered the nk2 cache file so I'm not sure if
I blew away every trace of the software. Any help is greatly appreciated. I
am willing to try anything at this point.