Xbee pro + Wireless SD shield

Hi Guys I am new here and getting started with a new project working with Arduino UNO+Wireless SD shield+Xbee pro ZB.
I will need the coordinator node link with a GSM/GPRS shield (this one looks promising http://www.cooking-hacks.com/index.php/arduino-gprs-module.html) so that it can upload data into my server.

I have seen this :Wireless Sensor Networks Research Group
My problem is can I stack the wireless SD shield (with Xbee and SD card) on Arduino, and the the GPRS shield onto the wireless SD shield?
Which pins are used by the wireless SD shield? Any conflict with the GPRS shield?

Check the documentation for the cards you want to use.

Mark

Thanks Mark. I found out that the wireless SD shield use SPI bus of the Arduino, and pin 4 as CS.
This is compatible with the GPRS shield of Seeeduino.