Dude. post some code. for God's sake.
if you actually are sending Xbee commands in the format you speficied in your last comment-
XBee.println(ATKYWORD);
Then that's wrong. I can't speak from personal experience as I have never used an XBee, but I've used a couple of other arduino shields that recieve AT commands (3G shield, cell shield) and I know that those commands have to be enclosed in quotes within the serial.println command
i.e.
XBee.println("ATKYWORD");