Well, of course not. That would be “kiloJew”, equivalent to 100 minyanim in the Hebrew system.
I wouldn’t find them all that antisemitic. I mean they only want to kill one jew. 
I think you’re all making too much of this.
After all, there was a famous baseball player who despite his name, was not anti-beer.
While leaning towards offensive, and still considering ignorant trying to be badarse, I wouldn’t discount something from out of left field and the “jew” being totally incidental (and not even intended to be read as “jew”)
Classic example - people here assume the short form of my handle is “Ben” but infact it should be read as Beng Ang Mo (literal translation would be petrol head white guy). I have also use Username88 and hadn’t considered the negative connotations until a thread here (88 is a lucky number here, where I grew up there wasn’t a big nazi / jewish / war culture etc)
I would think the best would be to see how he behaves or simply ask him before taking any further actions.
I’d strongly suspect antisemitism, but would allow for the possibility of some other meaning I hadn’t considered. I’ve been happily proven wrong on a couple of occasions.
A few years ago I encountered someone on IRC with the nick “kike”. He turned out to be from a Spanish-speaking country and was using it as a diminutive form of Enrique (pronounced “kee-kay”). I explained the word’s uglier meaning and he agreed to change it to avoid misunderstandings.
More recently a co-worker from India came to the office wearing a wristband with a right-facing swastika on it. Now I know that it’s an ancient symbol used by many different cultures and was, in this case, a Hindu one, but I likewise recommended he cover it or pick a different symbol to wear to work. Someone was bound to misinterpret it at some point, and it could have led to troubles with HR.
Context is everything.
I’m pretty sure I encountered a player with this handle on online PS3 Black Ops Zombies, and felt I should blow them up (in the virtual world), call them a ‘w*nker’ and leave the game, just to be on the safe side.
Quite right. Here in Minnesota, we’d just think it was a fan of the 1960’s Twins baseball – an old guy, obviously, given the typos.
Woah. Gives Harmon Killebrew’s name a whole new dimension.
And damn you all for making my joke, already. I’m posting it anyway.