I recently set up a new Viviotech VPS and ran into an issue that was easy to fix once I realized what was happening, but difficult to debug. I set up Railo running on the Resin server using Apache as a front end with mod_caucho. In my httpd.conf file I had the following lines:

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1LoadModule caucho_module /usr/lib/httpd/modules/mod_caucho.so
2ResinConfigServer localhost 6800
3CauchoConfigCacheDirectory /tmp
4CauchoStatus yes
This causes Resin to handle all requests from apache. The resin configuration files tell resin which URLs to handle. I also had an SVN server set up so I had a configuration file in /etc/httpd/conf.d/ to set up subversion. All my SVN repositories are under the location /svn. So reading SVN repositories worked fine, but I kept getting "path not found" errors when committing new files. After debugging this for quite a while using Fiddler, and other means, I finally realized that Resin was actually handling the PUT http request and, finding no file, returned a 404. So to fix this, and simply have Apache handle any request to /svn/ I modifed my httpd.conf file as follows:
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1LoadModule caucho_module /usr/lib/httpd/modules/mod_caucho.so
2<LocationMatch ^((?!/svn/).)*$>
3ResinConfigServer localhost 6800
4CauchoConfigCacheDirectory /tmp
5CauchoStatus yes
6</LocationMatch>
then restarted Apache. Now apache handles any requests to /svn/* and Resin handles all other requests. Hopefully this helps future Googlers in need.