I am not sure about in other modules, in pos the transaction works ok however
1. We do not get a message returned that states accepted or declined. When I send a bad card number the system returns a popup that says "page in ... says" 1
2. The data remains in the payment popup window when you do your next transaction. It should clear and default to the payment method listed at the top of your list.
3. What about security? When not using https is passing data secure?
Just as a note: In zen cart the merchant data and total amount to pay is passed to https://secure.authorize.net/gateway/transact.dll
This may be a more secure method for most of us...