As well all know, someone named blubs is connecting to all servers and downloads all models/maps etc.
Is it possible to you just permban this nick? and if, how?

I think that's a bot.

blubs is the creator of the game Nazi Zombies Portable (a QW engine game) - see http://www.moddb.com/games/nazi-zombies-portable/news/weekly-update-52

It's likely that blubs is the default name for people who start the game up fresh after downloading it. No idea how they wind up on QW servers, but...

Admins can use the /banip command to ban the various "blubs" players via their IP addresses. There's no way to ban by nickname as far as I know.

See: /banip, /ban, and /banrem

Note that the /ban command just winds up banning an IP as you can see in your KTX directory's listip.cfg file, so... ;<

Blubs might just become the most legendary player noone ever saw actually play the game

That "nazi client" always joins the server with this specific infokey(devs will know what I'm talking about) *ver = dp .. an easy patch on mvdsv can fix this.