It's possible to write an IRC server that allows for messages longer than 512 characters (I have done this already), and most other IRC clients (X-Chat and irssi for example) support messages of arbitrary length. mIRC oddly enough does not.
This is patently false and also misleading. mIRC supports "arbitrary" sized messages, though if you have an on input script it would limit to 4k. mIRC will break up the lines into ~450-500 char chunks by default, but this can be disabled via options. What you are probably complaining about is the editbox beep that goes off when you go past the ~500 char length limit. This does not disable you from writing more, it's simply a notification that your line will either be truncated or split.
More important however, is the comment about servers being able to support >512 chars. Yes, you *can* write a server that supports arbitrary length lines. The reality, however, is that few servers actually modify this line length. Most networks limit lines to around 512.
Khaled doesn't control how IRC servers behave, so the idea making colour codes 6x longer on average is going to force IRC networks to increase their line length is false. It will simply mean users will only be able to fit a third to a sixth the number of characters in a message that relied on the heavy use of colours. It doesn't matter how long a line mIRC can send, because servers will still work the same way they have for years.
