Motorola DC Cable Box - using IR EXT IN


I would like to see if anyone had success using Roomie Blaster and connecting it to the IR EXT IN port of the Motorola cable box DVR? I have DCX3500 box and it does have that IR EXT IN port on the back which looks like a stereo 3.5" socket. Wondering if something like this would work if connected to the 3-port cable and Motorola cable box?

The port is meant for a receiver like this