Epson 1280 + Photosmart 1000 = Smiley Face

I have an Epson 1280 successfully installed (print/status monitor,
drivers, etc.) on WINXP SP1. It prints great. I also have a HP
Photosmart 1000 that I have been trying to install. After
installation, it functions and prints properyly - however, if I print
something on the Epson a smiley face comes out on the HP and it
crashes the Epson Status Monitor after the item has successfully
printed on the Epson. The Epson is connected via USB and I have tried
the HP with both USB and Parallel (no change).

Any thoughts? Thanks.