Since nobody bothered to answer, I'll report the answer myself. I've been testing for a couple of days now and am sorry to report that the hibernate lucene integration is in no condition to be used in production. Essentially it doesn't handle concurrency, at all. Not even on a single node. So forget about clustering. Trivial use cases produce lots of exceptions in the logs about locks and out of date indexreaders (needed for delete). As reported here (http://lists.jboss.org/pipermail/hibernate-dev/2006-October/000563.html), synchronization is still being worked on. It would be appropriate to mark the lucene annotations as highly experimental and list the known issues with respect to synchronized usage in the documentation and discourage all use until it actually works. The inclusion of the hibernate lucene classes in a production quality server is rediculous since essentially using it in a multi user environement is likely to trigger failure. I'll be executing my backup plan now. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3983657#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...