Well, if you have done *any* randoms, you probably can't get a match. The TA proxy does not (that I am aware of) check for duplication of blocks, so you get credited with everything on the TA page that goes through the TA proxy. However, when your work hits the dNet server, if you have cracked any randoms that others already have credit for, or if you have cracked any legitimate blocks that someone has already cracked as a random, you won't get credit for it.
However, if this is something that Mika can do, I would be interested also!