I bet a lot of them are copy/pasting your user name directly from auctions though rather then going to your user lookup. Not much you can do about those besides deleting them.

~ May ~ I'm brazilian and if you research "why tech crunch isn't going to brazil" you'll see how bad it can get if you do that to the brazilian flag... lol People here are annoying, I know, and they can get worse. You can answer back. "Não entendo português, apenas em inglês por favor." (I don't understand portuguese, english only please) If you need help, send me a message :)