bitcoin/bitcoin — pull request #974 by sipa (2012-03-22 03:52:34+00:00)
Title: Introduce explicit explicit -walletupgrade option

Do not automatically change the wallet format unless the user takes an explicit action that implies an upgrade (encrypting, for now), or uses -walletupgrade.

There is also another option -walletformat= that limits upgrades to version . When creating a new wallet, this number is used, or if it is absert, the latest supported format.

Third, the current wallet version number is reported in getinfo.