Question for the tech savy, Plugs on the back Yesterday when I pulled the back cover off to get at the mem card I wiped of a square piece of black tape and found a coaxial plug like the one for my XM radio. Sure enough under the other tape is another. What are they for? I can't find any accesories listed like an extension antenna or anything so I'm kinda curious. I have a PCMIA GPS card that uses a second supplemental antenna that would plug right into it but...I don't want to fry the phone or the patch ant.