From: <glassfish_at_javadesktop.org>
Date: Sun, 10 May 2009 23:51:32 PDT

I got the same exception & resolved the issue after 3 hectic days.Check if you are using I hibernate3. In this version it is req to explicitly mention the connection class name. Also check if the jar is in classpath. Check steps & comments in below link
     
http://hibernatedb.blogspot.com/2009/05/automatic-reconnect-from-hibernate-to.html
     
autoReconnec=true doesnt seems to work..remove from config file.
[Message sent by forum member 'kamalraja' (kamalraja)]

http://forums.java.net/jive/thread.jspa?messageID=345745