The < blocking-timeout-millis > property for a datasource determines how many milliseconds a thread will wait for an available connection before timing out. Do you really have so many threads wanting connections that some of them get timeouts? You might want to consider also increasing the maximum number of connections. If this isn't the timeout you were looking for, please post the console output for the timeout error, and the contents of your *-ds.xml file. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4000997#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...