Hi.
I have two copies of the same Bitcoin-QT wallet that show a different BTC balance!

These wallets have the same public address but one of them is missing a single 40mBTC receipt. When I put this address into BlockchainINFO, it shows all the six transactions including the missing 40mBTC deposit. I've tried doing a -rescan on the wallet missing the transaction but it didn't help.

How can this be and how do I rectify it?

I'm using Ubuntu 12.04.
Thanks