(Required) For any deployment, you need to install a web container, such as Sun Java System Web Server or Sun Java System Application Server. You can also use any open standard web server (for example, Apache). In all cases, the Instant Messenger resources must reside on the web container host.
The Instant Messenger Online Help
You must install Instant Messenger resources on the same host where the web container is installed. In an Access Manager deployment, you can install these resources on the Access Manager server’s host or on a different web container host. In most cases, the resources will be installed on the same host where you installed the Instant Messaging server software. It is possible to locate the Instant Messenger resources on a host other than the Instant Messaging server or multiplexor.
Install the web container before configuring Instant Messaging.