Changing passwords in a WPM transaction via script?

So we are trying to setup a lot of transactions (over 100 initially but far more then that in total) that all have different logons. We need to come up with an automated way to update the account logon passwords when needed. Has anyone found a reasonable way to do this? It looks like it makes the password a variable in the recorder but I have not found a way to access that variable value via the API. I was thinking about scripting out a XML file create and replacing the old transaction with the new transaction every time but we would lose all the data gathered by the old transaction which is not what we want to do.

Any ideas would be appreciated.

Thanks

-Jim