Kind of with AMB on this one (and I know it's wrong...I've got the bath running and getting ready with the bleach and metal scouring pad) but personally I would just leave it as it is and just avoid the guy from now on.
There's little point about making post's and getting irate over it, if he's going to continue like that he's going to get found out soon enough, but then I'm a believer of Karma in it's most simplest of forms