Prepared statements are connection related entities,
and as such are managed by JDBC / your datasource
and not by JBoss. JBoss can be configured to use
connection pooling and when this is configured
properly and prepared statements are used then
you should see a performance improvement with
prepared statements. As a result ensure that your
server is configured properly for connection pooling.
Try setting the pool size to 1 connection and issuing
the same sql statement several time. If the same
connection is returned then you should see a performance
Hope that helps.