I made a rather weird "discovery" when I was playing around with the easiest lock in the world. The Master Trigger lock (http://www.masterlocks.com/item.asp?CID=1562). I found out that if I only SPP the 3the pin it will actually open, without even touching the other 3. How is this possible?
Possibly not (though I bet you are at least a little) but if it is cut low enough it might just be always open. Do you have the key? Is there a big dip in the key where the fourth pin would be?
LOL, didn't even bother look at the key before, I consider it unfair to the lock XD. Pin 4 is cut at 8, that explains XD cuts for pin 1 and 2 look like there a 1 and a 3, would make sense....