Sakai installations should always be accompanied by a fresh install of Tomcat. It provides a clean environment that simplifies troubleshooting if problems are encountered during the startup phase.
Sakai 2.7 8 out-of-the box (OOTB) will not run inside Tomcat 6.0+.
The Apache Tomcat servlet container provides an ideal environment for running Sakai as a web application. Tomcat implements both the Java Servlet and JavaServer Pages (JSP) specifications and can be run in standalone mode or in conjunction with a web application server such as the Apache HTTP server or JBoss. Sakai 2.7 works with the Tomcat 5.5 series.
We recommend Tomcat 5.5.33 in order to avoid certain Tomcat security vulnerabilities present in earlier releases.
Note however, that using Tomcat 5.5.27+ requires the addition of a JAVA_OPTS parameter (see below). Sakai 2.7 is not compatible with Tomcat 6.0+.
Tomcat can be downloaded as a binary install from http://archive.apache.org/dist/tomcat/tomcat-5/
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Good: C:\opt\tomcat\, C:\sakaistuff\installs\tomcat\ 
Bad: C:\program files\tomcat\, C:\opt\apache tomcat 5.5.3133\
Tomcat permissions
Unix/Mac users should make sure that they have write permissions to the Tomcat servlet container files and directories before proceeding or startup permission errors may occur.
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