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I really need help debugging an error I'm getting with Passenger on Apache.

I've just made a fresh install of Ubuntu 10.4 and have Apache, Ruby and Passenger installed. I'm trying to run a simple rack app but keep getting this error in my Apache error.log

[Tue Sep 28 05:54:41 2010] [error] [client] Premature end of script headers: 

The error then continues with

The backend application (process 25574) did not send a valid HTTP response; instead, it sent nothing at all. It is possible that it has crashed; please check whether there are crashing bugs in this application.
*** Exception NoMethodError in PhusionPassenger::Rack::ApplicationSpawner (undefined method `call' for nil:NilClass) (process 25574):

I've tried older versions of passenger also but get the same error.

  • Ubuntu 10.4
  • Apache 2.2.14
  • Ruby 1.9.2-p0
  • Passenger 2.2.15
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Have you checked to ensure that all of the config files used by your application are populated? (related)

share|improve this answer
Bizarre. My file was perfectly valid. However, until I separated it into a and a separate app.rb file it failed. – fatnic Sep 28 '10 at 9:54

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