Pywallet is a python utility that dumps addresses and private keys from a Bitcoin-QT or bitcoind wallet.dat file. The script also imports private keys into the wallet.dat file.
The importprivkey command makes some of pywallet's features unnecessary. The importprivkey command has been Included since version 0.6.0 of Bitcoin-QT and bitcoind. It is advised to shut down any program that is accessing the wallet.dat file and make a backup before running pywallet to avoid any potential for corruption.