So I think you should put the NickServ text in several languages in the mIRC database.
This is something that I am completely against, for reasons that I have already explained in my previous posts. I will not make such a feature work based on checking for specific words in an event. Implementing a feature in this way is worse than using a server version number to decide whether to enable certain client features, which is what numeric 005 was meant to resolve.
The current issue is due to this feature being badly implemented on the server side. The server coders implementing this should have realized that clients need to have a clear way of detecting events like this, as opposed to requiring clients to implement hacks that can break across languages, ircds, ircd versions, and so on.