Beware of ArgoUML. It's broken in important ways (object ID's get lost, property pages don't work, it loses your drawings, etc. etc.). I used it for the beginnings of a project (twice, with 0.8 and 0.91) and stopped using it after it had lost my work (twice) and saved itself in a mode it wouldn't open. I was on the argouml mailing list for a while, and the developers there seem to be banging away on their different corners without getting a handle on underlying design problems. Their UML parser comes from a different group, and every time the UML parser changes, Argo breaks. I suspect that the design needs a serious re-thinking.

(I wrote a Perl script that will diagnose broken Object ID's in Argo output files, if anyone's interested)

If you want a resonably stable diagramming tool that outputs a parseable file format, you might look at TCM (though it only runs on Unix systems under X Windows).

My approach to this was to write my own UML editor in Squeak. If you have Squeak, you can get a taste of this editor by looking at the NK-ConnectorsDemo.056.pr project on Bob's Super Swiki (via the FIND button in the Squeak Project Navigator).

I am building this into a real product. I am, however, unclear as to exactly what support I could provide for Perl in it. Perhaps someone has some suggestions.

I have also built a Perl module for accessing Rational Rose models via its OLE Automation interface; if you're interested, contact me.