Hi Monk, Thanks for notifying. Its true,initially I was trying to hit the test link when I could not get any apropriate responses I shifted to production just for trial. I did not get what u mean by "I've narrowed it down to the custom headers that are being built". To get through the problem I looked at their perl SDK kit they have given on their site : http://www.paymentech.net/download/) it is pretty much complicated. When I passed my XML request to their testing script edriver.pl it was giving successful response. Surely I m missing something in my code to get the proper response. If u have any ideas regarding this implementation please advice. Thanks, SHAM...