Two things have to be DONE for TOMCAT to ACKNOWLEDGE SSI scripts: 

1. Rename $CATALINA_BASE/server/lib/servlets-ssi.renametojar to $CATALINA_BASE/server/lib/servlets-ssi.jar. 

2. Uncomment the section of web.xml found in $CATALINA_BASE/conf/web.xml that DEALS with SSI. it looks like this when it is uncommented: 

<servlet>
<servlet-name>ssi</servlet-name>
<servlet-class>
org.apache.catalina.ssi.SSIServlet
</servlet-class>
<init-param>
<param-name>buffered</param-name>
<param-value>1</param-value>
</init-param>
<init-param>
<param-name>debug</param-name>
<param-value>0</param-value>
</init-param>
<init-param>
<param-name>expires</param-name>
<param-value>666</param-value>
</init-param>
<init-param>
<param-name>isVirtualWebappRelative</param-name>
<param-value>0</param-value>
</init-param>
<load-on-startup>4</load-on-startup>
</servlet>

Two things have to be done for tomcat to acknowledge SSI scripts: 

1. Rename $CATALINA_BASE/server/lib/servlets-ssi.renametojar to $CATALINA_BASE/server/lib/servlets-ssi.jar. 

2. Uncomment the section of web.xml found in $CATALINA_BASE/conf/web.xml that deals with SSI. it looks like this when it is uncommented: 

<servlet>
<servlet-name>ssi</servlet-name>
<servlet-class>
org.apache.catalina.ssi.SSIServlet
</servlet-class>
<init-param>
<param-name>buffered</param-name>
<param-value>1</param-value>
</init-param>
<init-param>
<param-name>debug</param-name>
<param-value>0</param-value>
</init-param>
<init-param>
<param-name>expires</param-name>
<param-value>666</param-value>
</init-param>
<init-param>
<param-name>isVirtualWebappRelative</param-name>
<param-value>0</param-value>
</init-param>
<load-on-startup>4</load-on-startup>
</servlet>