Currently I'm using MultiBit and have resorted to sending myself arbitrary amounts around the division points I think I need, but I have no way of seeing how my wallet is broken up currently.
To split your wallet so that you have many inputs with a smaller granularity, there is BTCRelay:
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http://btcrelay.com -
http://bitcointalk.org/index.php?topic=60603.0How that could be used is when sending the wager, give your BTCRelay address as the "custom Bitcoin address" payout method, and then have BTCRelay split that ten ways (or whatever you want) to addresses in your own wallet.