We're going to add Phusion's apt repository and get it all set up.
Update: March 13th 2015 Passenger 5 was just released, which is great, but is not backwards compatible with Passenger 4, which this guide originally assumed you would be using.
If you have already installed following this guide, you need to change the followling line in package in order for Passenger to be able to find the correct binary to use.
So it is much better to allow an "anonymous" access to the svn for redmine.
BTW: phusion passenger runs Ro R applications not neccessarily as the apache user!
The only change I did need to make to my redmine installation was a small adaptation of public/.htaccess: I moved all Rewrite directives into an block as Phusion Passenger deactivates mod_rewrite in it's standard configuration because of some compatibility problems.
If there are no good reason against running Redmine using Phusion Passenger I would like to see it mentioned in the Wiki as an alerternative to mongrel_cluster.
Memory usage of the server looks better as well (I moved to Ruby enterprise edition as well), but I want to wait a few days for more definite numbers.
Are there any known compatibility problems between Redmine and Phusion Passenger?
In order to access a subversion repository via self-certified SSL, I needed to accept a certificate, but couldn't figure out how to do so as the apache user, so I reverted to using mongrel running as root. it re-prompts every time, even though I accept it permanently).