Eclipse GEF
This article http://www.eclipse.org/articles/Article-GEF-Draw2d/GEF-Draw2d.html shows how to draw UML in GEF. It may be a good foundation for building a plug-in relationship editor for WSAD. This editor will represent web servers and app servers and the connections between them. The editor should be able to compile an xml plug-in configuration file to be loaded at each web server.