Worldpay callback failure

[trekker]

I have set every thing up (I think) according to the worldpay module instructions, Payment is made via world pay but the callback feature is not working it is turned on in worldpay admin, I also setup the email notification when a callback failure is detected, below is the email.

Please help

Our systems have detected that your callback has failed.

This callback failure means we were unable to pass information to your server about the following transaction:

Transaction ID: 98989898
Cart ID: osCsid=0af60f65b661611d70a0a4ef5af6eb3
Installation ID: 111111

Error reported: Callback to http://www.myserver.co.uk/dws/catalo...K?language=en: NOT OK, recevied HTTP status: 404
Server Reference: mggaeq3a:callbackFailureEmail-1179238:MerchReq-159

[trekker]

Read the instructions, it works, by requesting callback failure email from worldpay you will nitice that the FILENAME_WPCALLBACK looks like the line that I was supposed to add to the filenames.php file
define('FILENAME_WPCALLBACK....... as per the instructions.