Move command won't work with blockchain

[Leanerz]

Hi,
I use JSON RPC API of blockchain and when i try to use move function he return an error message ! Any one can provide a help ?

Thank's.

My code:
function pay($from, $to, $amount) {
$bitcoin = new jsonRPCClient('http://'.json_username.':'.json_password.'@'.json_server.':'.json_port.'/');
$move = $bitcoin->move($from, $to, $amount);
return $move;
}

Get an error from jsonRPCClient.php lib.