I've uploaded a new version of the code including a simple assembler in the svn repository. The old code is still available in cvs. The project als has been flagged inactive, since I don't think I'll update it any time soon.
The first release for this project has just been made available. It only contains an editor for eclipse 3.0 It currently supports a lot of features like:
-code completion for labels and equates
-hiding code you don't want to see
-outline of your document
What will probably be added for the next release is the ability to assemble programs inside eclipse itself.