When a web application is deployed to JBoss the context is initialised twice, this includes the context.xml in WEB-INF and the context in 'jbossweb-tomcat55.sar'.

This can be reproduced by deploying a web application with a valve defined in either of the context.xml descriptors, the valve will be deployed twice and will be invoked twice for each invocation of the web application.

The deployer in JBoss deploys web applications in a different way to the deployer in Tomcat. The Tomcat code is written to work both ways but when the JBoss approach is taken the initialisation code is invoked twice.

A fix has been applied to Tomcat that will be available in the 5.5.13 release.

http://issues.apache.org/bugzilla/show_bug.cgi?id=36802

Once the release is available the Tomcat version in JBoss should be updated.