mouser, I think it was just some random hex. Or maybe a serial number for an entirely different product, something physical, like a monitor or printer.
Phil usually isn't too kind to spammers and I thought this was a similar act of returning unwanted, rude behavior with equal (perhaps justified) rudeness as a way of saying "Go away! We don't want your kind here!"
In other words, I'm pretty sure Phil knows we don't advocate giving out registration codes and just gave doomandrei a serial number off of some other product. Giving him what he asked for (a serial number), but not really want he wanted (a serial number for the Spore Creature Creator program).