1: in my source code,"$bitcoin = new jsonRPCClient('
http://superman:{super}@127.0.0.1:8332/'" here superman is a username,and super is a password, are they the same as wallet encryption function of Bitcoin-Qt? i mean if someone steal the wallet.dat, but he doesn't know this password, can he send any coins out with the wallet.dat? if this is just an independent password of bitcoind daemon, then how can i set up a password for all out going requests just like wallet encryption function of Bitcoin-Qt?
You can access the wallet encryption via the walletpassphrase, walletlock, encryptwallet and walletpassphrasechange commands. The RPC password however is something completely different: it's only for authenticating the RPC call itself. Wallet encryption is independent.