motion, I know DX supports Multi-Monitor support since beta 1.99d
"...MultiMonitor support. Objects can now be dragged to other desktops and saved in
that position. IconX only functions on the primary monitor at the moment though,
but that's coming. "
That's from SD Central. But that's as far as I can help you, I don't know how to put it to work. But atleast you know it's there...