Vendor Master User Exit UM6MNT1R

To all,
Is anyone using the Vendor Master Maintenance User Exit program UM6MNT1R?  I am 
trying to use it and here is the problem I have run across:

1)    Security setup - Vendor Protected Data is LOCKED in the AM/AP application 
but is NOT LOCKED in the Purchasing application .
2)    Purchasing users are not authorized to the Vendor Protected Data in the 
AM/AP application but are in Purchasing. 
3)    Purchasing users are usually the ones creating new Vendors.

The Vendor Master User Exit only seems to get called when the user is 
authorized to the Protected data in both applications.  Just to make sure I was 
not imagining this, I changed my authority in AP and tested it again.  Also 
determined that if the user is not authorized to this data via AP, maintenance 
does not take affect.

Also found the same Vendor Protection in Purchasing is Locked, the same thing 
happens.  What is also strange is that you can be blocked from Vendor Master 
Maintenance in AP and authorized in Purchasing - even though it is the same 
program.  What's up with that?

I even went to the extent of modifying the file maintenance program, pointed 
out the lines of code required to change to MAPICS, gave them this scenario to 
test and they could not replicate and, therefore, did not fix it.  Just closed 
out the problem #.

Thanks...
Eric

P.S.  Sorry for the venting about the change in fix response from MAPICS...