Hard to say...
I've used an RAC for some things, but they have always said Avaya. I've heard that you have to have the proper revision for what version you have (I've used the same card for R5, R6, and R7, so that may not be true, but the card I use says 2002 on it, so it may be that the most recent revision is backwards compatible).
The thing to keep in mind is that PC administration for Partner systems is limited. You cannot change things in real time, nor can you program Voicemail with it (you can do a VS with a seperate program)
I really only use PC administration for inital programming, or to work on a system that may be, say, 3 hours away. But for tweaking, I generally use the keypad on the phone.
And by the way, I'm glad you were able to get it working on your own after all. We really only were trying to help. I cannot tell you how many times we've had to clean up a mess from someone who tried to "do it themselves" and ended up needing help anyways.
If the boss wants PC administration, he should spring for a RAC though.