My rails applications don't work!

Hello,
When I install rails applications on dreamhost such as Typo or Mephisto they work.
My own scripts work perfectly on my localhost but when uploading to dreamhost I get an Application Error message:
“Application error
Rails application failed to start properly”

Any idea ??

There may be some hints in this wiki entry:

http://wiki.dreamhost.com/index.php/Ruby_on_Rails

Wholly