Portals in FMP 5 and FMP 6

I'm presently using FMPro Unlimited 5.0 v3 to host a solution on a Mac Server running os 9.1. I have one db (main.fp5) that contains several thousand records and another db (subs.fp5) that contains over 100 records. In main.fp5 I have a portal that shows the subscriber's id (Field: SUBSCRIBERID) when the field MAKE in main.fp5 matches the field MAKES in subs.fp5. The field MAKES is a calculation that consists of the name of each make of automobile selected by the subscriber.

The portal in main.fp5 works as expected and shows all of the subscriber IDs associated with a particular make.

The only problem is that when a Find is performed on main.fp5 with a subscriber's ID entered in the portal I am only finding the records associated with the subscriber's first selected make. For instance, if a subscriber selects Acura and Honda as the types of records he would like to view, a Find performed in main.fp5 using that subscriber's ID in the portal is only turning up the records for Acuras.

When I copy the db's and run them in FMPro 5.5 for Windows the Find works as expected and finds all records for Acuras and Hondas. I also confirmed that a Find performed on the portal works the way I expected in FMPro 6 Unlimited on a Mac.

So, I know that my portal is set up right and that the results I expect to achieve can be achieved, but what is the problem with FMPro 5.0 v.3?: Is there something I am missing or is this just a flaw in the software?

Any thoughts or suggestions would be welcomed.

PS: I can't use FMPro 6.0 v.4 because my CDML solution that works using 5.0 crashes my Mac when I use 6.0. That's a whole other bag of worms I'll tackle later.