Stack GSM/GPRS Shield on top of GPS Shield

Hi, anyone can check for me if has any pin conflict if i want to stack this shield below :

[Comsat GSM/GPRS Shield

or

[Arduino GSM Shield

with

[Adafruit Ultimate GPS Shield

What i’m confused is [Adafruit Ultimate GPS Shield use Pin 7 and 8 for Sofware Serial while [Arduino GSM Shield use Pin 2 and 3 for software serial and Pin 7 for Modem Reset. Is that ok if i stack this 2 shield because Pin 7 was used on this 2 shields for different task?

If i’m using this shield, [Comsat GSM/GPRS Shield, it not give any problem i think because that shield have jumper setting to choose digital pin you want to use. Anybody can help me verify that this two shield compatible if i want to stack with [Adafruit GPS Shield. I want to make sure if there any pin conflict.](Overview | Adafruit Ultimate GPS Logger Shield | Adafruit Learning System)](ftp://imall.iteadstudio.com/IM120417009_IComSat/DS_IM120417009_IComSat.pdf)](http://arduino.cc/en/Main/ArduinoGSMShield)](Overview | Adafruit Ultimate GPS Logger Shield | Adafruit Learning System)](Overview | Adafruit Ultimate GPS Logger Shield | Adafruit Learning System)](http://arduino.cc/en/Main/ArduinoGSMShield)](ftp://imall.iteadstudio.com/IM120417009_IComSat/DS_IM120417009_IComSat.pdf)