Multibit backup created partial transactions!

[indu]

Here's what happened. I took backup of the following:

 savings.wallet
   savings.info
   savings-data (and all its contents)

Then I connected to internet, started my MultiBit. The wallet was open by default. There was a new deposit transaction.
I closed the wallet. Opened my backup wallet, to see if it can pick up the new transaction.
When I opened the backup wallet, it can recognize only until when backup was created. It doesn't recognize the new transaction when synced.

When I have two copies of the same wallet file, one recognizes the new transaction while the other sees all transaction except the new one.
Why would this happen?