As per my knowledge, one simple way of doing it is having multiple
<Host> tags in your server.xml. Like as follows
Code:
<Engine defaultHost="www.WEBSITE1.com" name="Catalina">
<Host name="www.WEBSITE1.com" appBase="/usr/share/tomcat5.5/webapps/WEBSITE1">
<Context path="" docBase="."/>
</Host>
<Host name="www.WEBSITE2.com" appBase="/usr/share/tomcat5.5/webapps/WEBSITE2">
<Context path="" docBase="."/>
</Host>
.....
</Engine>
And for information about virtual hosting go through following links
http://tomcat.apache.org/tomcat-6.0-...ing-howto.html
http://www.ex-parrot.com/pete/tomcat-vhost.html