There is a very relevant post on cocoon-dev today.

Torsten and Sylvain spoke to Cliff at ApacheCon
about a similar scenario for Cocoon.

http://marc.theaimsgroup.com/?l=xml-cocoon-dev&m=115201663025186
http://thread.gmane.org/gmane.text.xml.cocoon.devel/65071/focus=65163
Message-ID: 44AA60CD.9000706 () apache ! org

-David