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From back in time I spot this question, and have an answer.
I had the same question and called Desa International, the makers of Heath/Zenith lights.
You need 3 conductor wire between the fixtures. Red is the control line - just connect it on all lamps. Wire all white to white, black to black and red to red. You can wire as many lamps as master of the others as the circuit will handle. On interconnected smoke alarms, there is a control wire. I bet motion sensor lamps at similarly.
Bill