Running on Mac OS 10.4

[Walter Thompson]

We are trying to run Tomcat 6.0.16 on Mac OS 10.4.11. Installed using
download, followed instructions. Tomcat welcome page doesn't display.
 
Also getting error Message: Exception in thread "main"
java.lang.NoClassDefFoundError: org/apache/catalina/startup/Bootstrap.
 
Does anyone have a clue what is causing the problem?
 
Thanks for any help!
 
Walter Thompson