Looking at the
original Bitcoin client API I noticed one thing: once a wallet is encrypted with
encryptwallet, there does not seem to be an API call that unencrypts the wallet. Sure, you can change the passphrase with
walletpassphrasechange, but the encryption remains. Am I missing something, or is
encryptwallet really a one-way street as far as the API is concerned? (One could of course restore an unencrypted wallet from a backup, but that's not in discussion here).