GWT - Graphical representation of a tree

I want to represent a Tree in my GWt Project in a another way as the standard graphical representation. Drag & Drop should be able. Like this one: http://s1.directupload.net/file/d/2603/yzo588bb_jpg.htm

Do you know a good GWT Extension to realize this? I have already looked at the Google Web Tool开发者_高级运维kit Gallery. Do you think something like this would solve the problem? http://gwtgallery.appspot.com/about_app?app_id=86

I'm using Raphaël Gwt for such graphic stuff. I've tried Vectomatic once, but it is no fun to write, because it seems like the author had no Idea what a namespace is (Several classes starting with OMSVG) and it doesn't "feel" like writing a java programm.

On the other side, with Raphël-GWT is a binding to a javascript-library, thus you have (llittle) Preformance tradeoff for loading an external Cross-browser javascript library.