You can create an Apache alias to add new urls. ( http://httpd.apache.org/docs/current/en/mod/mod_alias.html ). However, I do not recommend to modify the current ones in the apache configuration files. You might get some unexpected and untested behavior.

The answer given will only work if subsequent http fetches are allowed to access the original urls.  I need to make a change where the entire app changes url to http://<ip/host>/new_path_part/original_path.  I use apache for proxying incoming requests from the world.  Redirection to various servers is based on what above is referenced as new_path_par.  Wordpress, Drupal and Bugzilla allow for easy additon of a "new_path_part" so proxying them is easy.  Have not been able to figure out how to do with GetStack.  Most important part is Apache does not do alterations to urls contained in responses so change needs to be made to GitStack.  Suggestions anyone?