From the mIRC website, “Of course this new version addresses the buggies and most of the other comments and remarks we received after the previous release. Apart from that Khaled spend lots of time on the UTF-8 support that was added in the previous version. As you might know UTF-8 is a font encoding system that allows you to use fonts with strange, international characters. That of course helps a lot if you want to chat in your own language!”
See the shizzle at http://www.mirc.com/ awesome.