Http posting xml with special character


I am trying to integrate Siebel and webmethods. My input parameter is a string called $xmldata. Siebel is able to send to webmethods an xml properly, until they send xml’s conataining special characters (e.g. &). Siebel is sending this xml through http and is converted into a & format. unfortunately when i try to get string from the pipeline it shows that the xml being sent by Siebel is truncated each time it sees an “&”.

I have tried changing my input parameter to a node, but this still doesn’t work. any suggestion on how Siebel or webmethods should configure the ampersands?