Thank you SOOOOO much guys!!
Great feature! Finally I can now use a different charset for non-unicode applications (e. g. Hebrew) and true Unicode apps (foobar2000)!
This is important if you have French Windows but you want to search for music in Hebrew in Soulseek, which is non-unicode (unfortunately).
BUT ... the "Multibyte editbox" option is extremely confusing. It does not tell anything to me, so if I had not read this forum thread I would not have got it working, as UTF-8 enabling is NOT sufficient. I suggest that you do not bother the user with such things and remove it, enabling this internally when the user wants UTF-8. My 2c. mIRC is an application mainly for chats, and if you want to chat in foreign characters, this "Multibyte editbox" is mandatory! Otherwise you will get a lot of question marks in the channel, and users will complain they do not get the characters right.