Well I edited the PHP.xml, so ALL (http://www.php.net/quickref.php) php functions will be colored now, including non-standard extensions like mcrypt, PECL extensiosn etc.

How to install (Well, what I did and worked so far):

Download the PHP.xm.zip
Goto: C:\Program Files\Adobe\Adobe Dreamweaver CS3\configuration\CodeColoring\
Find PHP.xml and change the name to: PHP.xml.bak
Extract the PHP.xml.zip into the same folder above
Restart the Dreamweaver


Might work with older versions as well, not tested.

Enjoy :)