XML-based language for behavior?

Can you recommend an XML-based language for specifying behavior, e.g. for process management, workflows, et开发者_JAVA技巧c.? So far I've found YAWL. Can you suggest some alternatives also? Which XML-based language would you use if you wanted to build your own workflow engine?

BPEL : http://en.wikipedia.org/wiki/Bpel

JPDL : http://docs.jboss.org/jbpm/v3/userguide/jpdl.html

XPDL : http://www.xpdl.org/

...

workflow control patterns : http://workflowpatterns.com/patterns/control/

...