Outlook Shared Calendar: Who?

I have searched deep for solutions to this without luck…

I have a shared team calendar (not public calendar) in outlook (2003) in an exchange environment with a team given the ability to create new entries and to only edit their own entries.

As the owner of the calendar (my calendar is the one shared) how do I find out who created the entries?

I know the info must be stored somewhere because they’re only allowed to edit their own creations.

Any help or pointers greatly appreciated (either through the GUI or through programming).

Dave.