Sounds like this would have to happen at the OS level. Maybe find some sort of parental security app that stops children from running certain programs.

Hhm, i appreciate your response but i mean on a server level for example if someone connects using a web client like LightIRC and they use a certain userid that is assigned to the applet in the code, if someone decides to create a custom applet for your server using a different userid or if they use mIRC in general would it be possible to auto Kline them?

If you have the proper O-line and flags, you can CTCP Version on server join and and Kline accordingly.

Awesome could you make a script for it for me please.

CTCP Versions can be spoofed so it would be rather impossible to pull off 100%.