XPS 420 IR Blaster

I recently decided to hook up a cable box to my XPS 420 and realize I never got an IR blaster with the system.  I have the remote and IR receiver for the remote that came with the system but never got an IR blaster that plugs into the back of the receiver.  Because of this, Media Center won't let me finish setting up the cable box to work with the system.  Wasn't the the IR blaster supposed to come with the XPS 420?  I ordered it with the ATI 650 TV tuner, Media Center remote, and IR receiver but never got the IR blaster.