could be nice idea, though will be problomatic for implanting as the php/code syntax highlighter is based upon internal php function called highlight_string().
you can see more info @
http://php.benscom.com/manual/en/fun...ght-string.php
to make such i guess it will require to create similar function to make alot of reg-exp matched for key words & replace it with some color or <font> tags.
it can be nice idea indeed to have. i'll try to look closer into it when i'll have some free time - if anything will be coming through towards working beta (not making any promise) i'll keep you posted.