I've developed an application on my machine using tomcat 6.0.18, Java 1.6 and Hibernate 3.
Works a treat!
Until I went to pass the WAR over to a remote server running Tomcat 5.5.25
The application loads and works for a few queries to the database but then throws
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
I don't think it has anything to do with the remote servers setup or mysql has anything to do with it.
As I installed Tomcat 5.5.25 on another local machine and could recreated the problem.