SQLStorage is dead - long live RDBMSStorage!
Archetypes-based content-types are traditonally tied to the ZODB as backend storage. It has always been hard making the content available through a RDBMS - the only solution for a long time has been SQLStorage. However the implementation and the behavior was more than flaky. Lately projects like collective.tin (Laurence Rowe) and Contentmirroring by Kapil appeared on the scene.