Weird double-order with paypal

Hello all -

I wasn't sure where to post this, so I'll put it here and if it needs to be moved, so be it.

I recently received an order from a customer who paid with paypal. The order, however, came through twice on zen cart, even though there is only one payment in Paypal. But then it gets weird.

Here's what the extra order shows for info:

First Name: deleted
Last Name: deleted
Business Name:
Address Name:
Address Street:
Address City:
Address State:
Address Country: US
Payer Email: deleted
Ebay ID:
Payer ID: deleted
Payer Status: verified
Address Status: confirmed
Trans. Type: web_accept
Trans. ID: deleted
Parent Trans. ID:
Payment Type: instant
Payment Status: Completed
Pending Reason:
Invoice:
Payment Date: 12/31/1969 18:59:59
Currency: USD
Gross Amount: deleted
Payment Fee: deleted
Exchange Rate: 1.00
Cart items: 0

Why does zencart think a payment was received in 1969?

Interestingly enough, the Trans. ID matches for both orders.

It's really not a problem for me - I'll just delete the extra order - but it confused my customer.

Any thoughts?

version 1.3.8a

Assuming you're using the "PayPal Website Payments Standard/IPN" module, try this: http://www.zen-cart.com/forum/showpost.php?p=484125&postcount=3