What have you tried so far?
Tomcat can be configured using Preferences->MyEclipse->Servers->Tomcat->Tomcat 6.x. If you put the Tomcat home directory in the main preferences panel, many other fields will automatically be filled in. Don't forget to click the Enable button at the top.
There are sub-pages for other preferences.
If you have further problems, try posting on the MyEclipse web site (
http://www.myeclipseide.com/index.php?module=PNphpBB2). The support team are usually pretty good at responding.
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