I installed:
I had a same problem. Timo is right.
your application must set /home/rvm_user/ directory.
example:
# vi /etc/conf/httpd.conf
LoadModule passenger_module
/home/rvm_user/.rvm/gems/ruby-1.9.3-rc1/gems/passenger-3.0.9/ext/apache2/mod_passenger.so
PassengerRoot /home/rvm_user/.rvm/gems/ruby-1.9.3-rc1/gems/passenger-3.0.9
PassengerRuby /home/rvm_user/.rvm/wrappers/ruby-1.9.3-rc1/ruby
ServerName www.yourhost.com
DocumentRoot /home/rvm_user/your_application/public
AllowOverride all
Options -MultiViews
# chmod 755 /home/rvm_user/
# /etc/rc.d/init.d/httpd restart