I'm not sure what your problem is. I downloaded Trac not long ago, and Haskell highlighting worked out of the box for me after installing Pygments. Here's the proof (this is the wiki of a course I'm teaching): http://kfarkas.iit.bme.hu/trac/bfp/wiki/EloadasAbsztrakciok1 The code to activate it is the following: {{{ #!hs main = print "Hello world!" }}} Gergely -- http://www.fastmail.fm - One of many happy users: http://www.fastmail.fm/docs/quotes.html