For Xcode 3 there is plenty of information available about how to define a syntax highlighting specification for a language not already supported in Xcode. But there doesn't seem to be any information on how to do it for Xcode 4. For example, I would like syntax highlighting for Common Lisp, Forth, and other languages not appearing in the "file type" drop down in Xcode 4.
There is a project called solarize that may do what you're looking for, but I didn't see any of the languages you listed and support for Xcode 4 is still limited. I personally use Xcode only for Objective-C programming, and then use eclipse or TextWrangler for the rest
Eclipse is great for the more intensive projects, that have multiple classes, and are actual projects. It's mainly developed for Java, but also supports Python, C/C++, PHP, and Lisp (probably even more)
TextWrangler is great for small edits or files. Things that I need to pull up quick, and make smaller edits to and supports tons of languages as well.
It appears that Xcode can even open external editors when the files are associated to that editor. While this isn't the perfect solution, it appears to be the only one for now.