Actually, what Graph::Easy does (although untested so far for GraphML data) should suffice. But as I'd like to present the result on a webpage, it would be nice if the graph is rendered a little bit more nicely than for example the Graph::Easy ASCII output.
That's what I meant by "draggable": a graph that floats around a bit, can be turned and zommed around, like http://www.aharef.info/static/htmlgraph/?url=http://www.google.com, but by using a generic lib.