Outlook 2003 Delegates

I have a user who needs to delegate their mailbox. Getting to the delegate selection is no problem.
Tools > Options > Delegates (tab) > Add
PROBLEM:
In the “Show names from the:” window, there is only one (1) option. In this case, it is NOT the Global Address List.

My question is what/where/how can that option be modified so that the user can select the Global Address List.

Additional info: I have checked other users, and each one has a different possibility. Two are able to use the GAL, but two others have something else. In all cases there is only one selection, the drop down window does not allow any other selection.

Any help would be most appreciated.