Visitors Visa Extension

I'm not sure if this is the norm these days, but this is what happened. My parents came last September (they had a 10 yr visa), at the airport they got a 6 month visa which was supposed to expire March 15, 2006. 6 weeks before March 15, I appled for a 5 month extension. I got a receipt from USCIS dated Feb 15 (this date is a month earlier than their original visa expiration date). But we never got approval notice till now, my parents stayed till July 16th (we just assumed we'll get approved) and went back. Still we dont have any communication from USCIS, I called them and get the machine everytime, it says their representatives dont have more info than the automated message. If anyone has experienced something like this or would like to give any feedback, I'll appreciate that, please email me at '[email protected]', thanks.