The options that you are passing in the last json object are: gaslimit and value of Ether to send along. These (and other configurable parameters such as the sender or the gasprice) are available via msg
and tx
objects as described here:
function EscrowPayment(address _seller, address _judge) payable {
gasLimit = msg.gas; // this is only the *remaining* gas and not the exact value that you passed
value = msg.value; // in Wei
gasPrice = tx.gasprice;
buyer = msg.sender;
seller = _seller;
judge = _judge;
}