I reported this a while back, and it was fixed for software mode.
It seems the bug still exists in HWA mode though.
Maybe it's just my computer, so can anyone check this out and see if you are getting the same results.
Run this mfa in HWA mode and check the amount of memory used. Then restart the frame and check it again. I seems to use 6mb more memory after every restart. The bug is less noticeable in DirectX 8 mode.
EDIT: I'm using mmf dev R249 B6