I was under the impression it was the wireless version, and it wasn't playing nicely with the Airport. But once swapped to USB, they were fine with one another.
I hadn't realized the USB port didn't work properly for you. I wonder what the deal was, as there's others with that printer that haven't had issues.
Who knows? It could be something simple, but I haven't found time to drag everything to a genius bar -- I still have 2 copies of everything in my iPhone contacts list, and that problem is at least a year old....