Monitor the number of connections in use, especially when this exception occurs, through the jmx-console. Access jmx-console at http://localhost:8080/jmx-console. On this page under jboss.jca, you will find a link like name=myDS,service=ManagedConnectionPool (where myDS is the jndi-name of your datasource). Click on this link and you will be forwarded to a page which will have the connection count and other details about this connection pool. Check out the number of connections that are in use. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4122501#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...