You need to have a <host></host> entry for each domain you want to run servlets for setup in the server.xml file.
e.g:
Code:
<!-- host 1 context's -->
<Host name="host.com" appBase="/home/host/public_html">
<Context path="" reloadable="true" docBase="/home/host/public_html" debug="1"/>
</Host>
<Host name="www.host.com" appBase="/home/host/public_html">
<Context path="" reloadable="true" docBase="/home/host/public_html" debug="1"/>
</Host>
<!-- host 2 context's -->
<Host name=".host2.com" appBase="/home/host2/public_html">
<Context path="" reloadable="true" docBase="/home2/host2/public_html" debug="10"/>
<Logger className="org.apache.catalina.logger.FileLogger" prefix="host2_log" suffix=".txt" timestamp="true"/>
</Host>
<Host name="www.host2.com" appBase="/home/host2/public_html">
<Context path="" reloadable="true" docBase="/home2/host2/public_html" debug="10"/>
<Logger className="org.apache.catalina.logger.FileLogger" prefix="host2_log" suffix=".txt" timestamp="true"/>
</Host>