Problem with Paypal IPN Orders Paid but not showing up

I'm currently getting this error message when trying to pay through paypal. I have search through some posts here before and I had done all of the things to try to fix this.

Perhaps someone can figure this out. Here is the error message and below it the description of my configuration.

Oct 17 2010 20:47 -- IPN INFO - POST VARS to be sent back for validation:
To: www.paypal.com:80
POST /cgi-bin/webscr HTTP/1.1
Host: https://www.paypal.com
Content-type: application/x-www-form-urlencoded
Content-length: 86
Connection: close

Array
(
[cmd] => _notify-sync
[tx] =>
[at] => XlR**********a0x5q
)

Oct 17 2010 20:47 -- IPN INFO - Confirmation/Validation response

5
FAIL
0

Oct 17 2010 20:47 -- IPN WARNING :: PDT Transaction was not marked as SUCCESS. Keep this report for potential use in fraud investigations.
IPN Info =
5
FAIL
0

1. The ipn handler is correct and is dated 2007-11-27
2. The return in paypal is set to on
3. IPN on in Paypal
4. Have premier account in Paypal
5. Payment Data Transfer is set to ON
6. Identity token matches in paypal and zencart
7. Paypal account optional is set to ON
8. Using version 1.3.8a of zencart
9. IPN check works fine no errors

HELP!!

a) You should really be upgrading to the latest version of Zen Cart. You're missing hundreds of important updates.
b) You should really be using Express Checkout instead of Website Payments Standard. You won't have any of those symptoms with Express Checkout.