When I add the product to my cart and finally press 'Confirm Order'
I have to wait for a long time and then the browser gets back with


The following error was encountered:

* Zero Sized Reply

Squid did not receive any data for this request

What might be the reason?
I am using Authorize.net AIM method and everything seems to be correct on the Admin side (Authorize.net) in the shop
I am hosted with godaddy
Thanks