Migrating from Websphere 6 to Tomcat 6

Last year we took up a project to migrate a J2EE infrastructure from Websphere 6 to Tomcat 6.
The applications are written using Struts and POJOs that access Stored Procedures on AS/400 via JDBC.
It took us just 4 days to complete the migration of 8 fairly complex applications.
4 Tomcat instances running on 2 Linux servers are load balanced via Apache 2.2 + mod_jk.

We have developed a custom application for the sysadmins to centrally manage all tomcat instances.
The application makes use of the tomcat manager application and JMX to control and monitor the tomcat instances

To complete the puzzle we are now testing our Terracotta to apply session replication to gain even higher avaliability!