Apache Tomcat Not Showing in Eclipse Server Runtime Environments

In my case I needed to install "JST Server Adapters". I am running Eclipse 3.6 Helios RCP Edition.

Here are the steps I followed:

1. Help -> Install New Software
2. Choose "Helios - http://download.eclipse.org/releases/helios" site
3. Expand "Web, XML, and Java EE Development"
4. Check JST Server Adapters (version 3.2.2)

After that I could define new Server Runtime Environments.

EDIT: With Eclipse 3.7 Indigo Classic, the steps are the same but you need both JST Server Adapters and JST Server Adapters Extentions to get the Server Runtime Environment options.