With a major project behind my back, I'm about ready to upgrade to 4.0. The only thing that concerns me is tomcat integration. We are still running Tomcat 4.1.x here and only now starting considering transitioning to 5. With IDEA 3.0, I'm using a custom TomcatIntegration plugin for Tomcat 4.1 which I downloaded from here (I'm sorry, I forgot who the author was).
What's the level of support for 4.1.x in IDEA 4? If it's not officially supported, is there a custom plugin like there was for 3.0?