I'm not sure, but I think you have to use an Apple Airport Express to do this.
Maybe an Apple TV2 could do this also, but it's really meant to be connected to a TV set via HDMI.
The Airport Express has a regular headphone jack but the Apple TV2 has only Optical and HDMI outputs.
You would use the Express as the remote and connect the speakers to it.
There may be some other way to use your wireless speakers.... Anyone?
Good Luck,
Keri