Ooooo... we have a volunteer! :)
For the record, we are in the process of moving the docs. See http://www.rhq-project.org... (so your link would be http://www.rhq-project.org/display/JOPR2/Content)
I think the big thing you'd need would be to convert the maven metadata into the common RHQ metadata language.
I wrote a utility that might be able to help (it defines a xml schema that describes an XML file that could contain RHQ content package metadata - if you can convert maven metadata to that kind of xml document, that would be some work that would need to be done).
Lots of work is going into the content subsystem and content server-side plugins, unsure how much of this has changed since I last looked at it.