You should only get this if your webapp's web.xml file includes a element. Remove that element and your webapp will not be clustered.
Argghh.... element you need to remove is "distributable"
PS - Do i need to configure something to work with tomcat as web container?
You mean use Tomcat standalone, outside of JBoss?
Not sure; depends on your webapp. May be as simple as copying your war file into the tomcat webapps directory.
Given the name "TestDataSourceWeb", there may be datasource configuration involved. See http://tomcat.apache.org/tomcat-5.5-doc/jndi-datasource-examples-howto.html in the Tomcat 5.5 docs for some more info on datasources in Tomcat. There are similar docs for the tomcat 4.x and 5.0.x releases.