Good news!!! I've just found this: http://www.eclipse.org/bpel/: A designer tool for the BPEL...
Which is an answer to my previous post.
I am surprised that is not mentionned anywhere in the JBPM doc. Probably, just a question of time! I think some link to this should be added in the JBPM documentation. At least in the BPEL extension documentation or in the GDP doc.
And thanks for the work!!!
I think there is a small term confusion: graph representation != graphical representation. Graphs are mathematical structures. Structured activities in BPEL (sequence, if, while, flow, pick, etc.) are "unfolded" by the jBPM BPEL parser into nodes, transitions and links. Graphs have a graphical representation, but the math concept is a separate thing.
My apologies if I am saying something you already knew.
Regarding the Eclipse designer, as a matter of fact, we are in touch with the developers behind that initiative and are working on an implementation of their runtime framework for jBPM BPEL. That might take a while as the runtime framework is not even there, but, as you say, this is a question of time.
I will link to it from the documentation so that our fine users are aware there is an open source designer on the works.
Thanks for your suggestions.