EDIT: Sorry, accidentally posted before finishing my post... hold on
EDIT: ok,
Now I see that doing a member search for 'mami28' sends you to the profile for that account, and that account has been deleted or banned or whatever, so it gives an error. I tested it a bit and if you search for a username that's never been used, it gives a different kind of error.
I'll admit now that I started to suspect Jeff, because I wasn't sure how he got the link to that profile. I apologise for that.
@Golapagos
mami28 is the account that the person (who tried to steal my minecraft account) tried to register on this site.
And I registed on this site today simply so I could post this thread.
Anyway I'm going to contact Mac now