eWAY....ugh...

I've done a search for eWAY related topics both here and on Google, and I see a lot of people with problems, but none of the threads ever seem to conclude with answers.

I'm using the latest Zen Cart, the latest FEC module and the last eWAY module (from 2007). eWAY ID is entered correctly, switched to live so I could test some low priced sample items with a real card.

I add an item to Shopping Cart, Go To Checkout, Go To Payment, enter credit card details, hit Process Order -- then it takes me to the FEC confirmation page, and then after 5 seconds reloads back to the Payment page with the items still in the cart.

Logged into Admin and the transactions show up as FAILED in the eWAY module history. Tried another credit card, same thing.

I followed install instructions to the letter, my SSL is valid, so I'm not sure what is going on.

Any ideas?