this patch was wrote a while ago when the latest stable tomcat was tomcat4 and 5 was in development, still maybe you will find it useful. im keeping it here, just in case :P :P

by default, when a request comes to tomcat without a file specified into url, tomcat will respond with a redirect to the browser or to search engine who made the request.this way of handling these type of requests isnt so good when its about search engines.
you can get rid of tomcat redirects to default folder index files if you apply this patch to jakarta-tomcat source tree and recompile DefaultServlet.java class.
how to update your tomcat server:
1. download the jakarta-tomcat source
2. apply the patch to source tree
3. recompile DefaultServlet.java class (export in your classpath var the path to servlet.jar, then cd into /path/to/tomcat/source/catalina/src/share and compile it: javac -sourcepath . org/apache/catalina/servlets/DefaultServlet.java
4. update the runing tomcat with the resulted class file
5. register into your conf/web.xml the parameter hlNormalRedirect. if set to true, classic way of tomcat will be choosed. if set to false, your server will do internal redirects, skipping hard browser redirect.
6. restart tomcat service
its tested with tomcat 4.1.24 but should work as well on the other versions.