GPRS Shield used pins

I would like to know exactly which pins the GPRS Shield uses so that I can work around those pins when I start stacking more boards on top of it (really glad the designers made that possible with the female header extensions). If you are curious, I hope to add a wifi shield, Bees shield with Bluetooth and Xbee, a GPS shield, and a touch shield slide. So yes, a home brew smart phone. Perhaps it would also be relevant to define the functionality of the pins near the PWRKEY, I assume these affect what pins are being used. I couldn’t find the answers to these questions in the product page, and I couldn’t quite read the schematic well enough to have a clear definition, so someone please point me in the right direction. Thanks!!!

The schematic now is on the wiki, … .9_sch.pdf