name hack is possible on 2.1.0 but i dont know how to :)

Today i was on a private server when someone named <GM>Paurazzo began spamming in lfg channel. He was typing something like "hey guys im a gm, if you want me to fix some bugs send me 200 gold via mail" lol
I played in this server since it was born (my friend is a gm) and i never saw a gm called paurazzo, anyway i asked my friend, he said there isnt such a gm in the staff so.
I know that you guys always say that name hack is impossible but i saw that with my own eyes and im sure that:

1) He was not a gm
2) It was surely an hack
3) The server is a 2.1.0+ one
4) If important it is an Antrix private server

i think it is made using filters with wpe pro but anyway im askin you, people for sure more expert thn me

Sry for my bad english thx :)

not sure if it still exists but there used to be a bug that would place the GM tag in front of the name of a player when they are contacted by one. This is a possible reason for what you saw.

/2 . (insert as much spaces as needed here) (edit channellayout)<GM> Name: Text

wpe can do this!