curl_exec() hangs

Hi, I am using curl to send xml string to my merchant's account gateway when curl_exec() executes the xml is successfully received by its destination but I am not getting anything back (it just hangs) Could anyone help me with this problem? The following is my curl configuration: // TELL cURL TO DO A REGULAR HTTP POST. curl_setopt ($ch, CURLOPT_POST, 1); // PASS THE REQUEST STRING THAT WE BUILD ABOVE curl_setopt ($ch, CURLOPT_POSTFIELDS, $request); // TELL cURL TO USE strlen() TO GET THE DATA SIZE. curl_setopt ($ch, CURLOPT_POSTFIELDSIZE, 0); // TELL cURL WHEN TO TIME OUT //IF YOU'RE TIMING OUT BEFORE GETTING A RESPONSE FROM SUREPAY, INCREASE THIS NUMBER curl_setopt ($ch, CURLOPT_TIMEOUT, 3300); // TELL cURL TO INCLUDE THE HEADER IN THE OUTPUT curl_setopt ($ch, CURLOPT_HEADER, 0); // TELL cURL TO USE SSL VERSION 3. curl_setopt ($ch, CURLOPT_SSLVERSION, 3); // TRANSFER THE SUREPAY RESPONSE INTO A VARIABLE. curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1); Thank you, Jacek