Hi there

The people that help here, including the moderators and even the author of mIRC, Khaled, have no control over what happens on individual channels, server or networks. mIRC is simply a client that allows you to connect to those servers and join those channels.
If you have suffered from a channel takeover, then you will have to ask the network IRC Operators for help. Try
/join #Help and ask there on how to contact an IRCop, or check out the network's website - if you don't know the address, search
Google.
Unless it is some sort of Java chat, the nickname "¤õ¨®" is invalid, it cannot be used, even by a "hacker". On that subject, it is extremely unlikely that a "hacker" can take over a channel. The most likely explanations is that someone opped them (@) and they kicked everyone out and/or deopped everyone. This cannot be prevented really.
If the network has channel services (i.e. ChanServ) then the channel password may have been really easy to guess. In this case, it is the Founder/Owner's fault for not thinking up a good password.
Another possibility is that the founder/owner of the channel contracted a virus and the person looked in a script file or something and found the password to the channel. Unlikely, but possible. Again, this is the fault of the owner.
You can try using the channel service if there is one to gain your ops back. Again, ask in the #Help channel.
Best of luck

Regards,