NFC Shield V1.0 Didn't find PN53x board

Hello,

A couple of days ago I bought this shield: http://www.seeedstudio.com/depot/-p-916.html?cPath=132_134 (NFC Shield V1.0) and the Mifare-One RFID Tag (13.56MHz).
I placed the shield as described in the documentation, onto my Arduino Uno R3 and tried in onto the Arduino Uno R2. I uploaded the examples and all I see in the serial monitor is: Didn’t find PN53x board. I went through the documentation, I went through this forum in search for the problem, even on the ada fruit forums. But I am not able to solve the problem.
I also tried the other versions provided on the Wiki.

Edit # 1: The L led on the board remains ON, after booted. It does not flicker and does not goes off.

Would someone be able to help me out?

hello, the NFC Shield wiki is a little confusing and may lead to failture . pleae refer to wiki for Version 2.0:http://www.seeedstudio.com/wiki/NFC_Shield_V2.0
and download the related lib to try again . i am trying to clear up .