How do you mix Phusion Passenger in mod_perl virtual host?

I have a VirtualHost that sets up a handler for Location / PerlModule for deploying a catalyst app.

I want to convert catalyst app to rails, but gradually. The front end is all javascript using the ExtJS Framework and the backend only serves JSON. This will allow for a gradual transition if JSON is in the same format from catalyst and rails.

Ideally, I could do by placing both rails and catalysts in the same domain, and then update parts of my AJAX application to use rails instead of catalyst one at a time.

I need to have them on the same domain, so I don't have to recode all the AJAX components to use the script proxy and JSON Callback.

Any ideas on how to set up the phusion passenger to work with mod_perl that owns the location / and whatever it contains, if I don't specify another handler?

I tried to set the default handler for / rails to the default handler to bypass mod_perl and then use Passenger RailsBaseURI / rails ... but that clearly doesn't work. You cannot use RailsBaseURI on Location tag. I couldn't find any handlers to use with passengers.