Redmine

I believe it would be preferrable to use the google prettify syntax highlighter rather than Coderay for syntax highlighting in Redmine.
It has support for a much larger set of languages, and highlights the code clientside via javascript rather than serverside (so the pre-formatted code stays readable when looking at the source).

I have hacked support for this into our redmine installation, and the necessary changes (if letting coderay stay active as well) are minimal.

1. Copy the prettify .js files to public/javascripts/
2. Copy the prettify .css file to public/stylesheets/

Now, I'm not a rails coder, so the following step is probably not the cleanest solution. I'll describe it anyway for completeness:

3. Modify app/views/layouts/base.rhtml with the following changes:
    3.1. add onload="prettyPrint()" to the body tag.
    3.2. link to prettify.js and prettify.css in the header.
4. Put code in pre blocks with class "prettyprint".

Link:
http://code.google.com/p/google-code-prettify/