MyFaces is known to work with and was tested with the following environment: Java - JDK 1.4.0_01 - JDK 1.4.1 Servlet Container - Tomcat 4.0.x - Tomcat 4.1.x - JRun 4 SP1a JSF API - JSF-API from the JavaServerTM Faces v1.0 Reference Implementation Early Access 4