Talking Back With HTTPS Server

Hey, I working on an e-commerce project in which we are using iBill for real time credit card processing. I know how to talk to the iBill server, it is accomplished by using SSL to send form data (name="amount" value="35.50"). Once the info is sent posted to iBills processing script (https://secure.ibill.com/cgi-win/ccard/tpcard.exe) the server then respondes with something like "authorized","444333","10/7/00","15:20", and so on and so forth. It basically responds with the either authorized or declined and information regarding the transaction. Each piece of information is surrounded in double-quotes and is seperated by a coma. So, how do I get PHP to take the information iBill sends back and do something with it? I guess the main thing I'm unclear about is how to receive the data iBill returns, and how to split up the string into seperate variables so I can use it. Thanks a bunch.