i seriously doubt it, AWD has been available on the charger, 300, and magnum since 2006 or 2007, so i'm sure there would have been talk about it by now. As for retrofitting, who knows, seen crazier things happen!
on a side note, i don't know about the rest of you guys, but in the parts of California that i frequent, the highway patrol is using new explorers, and out here in Nebraska, the chargers are being fazed out already in favor of the Taurus and the new Caprice police cars.