title: log backtrace, rescue_from and custom error pages
body: <p>I am trying to create custom error pages in a project of 
  rails 3.0.20 and ruby 1.8.7.</p>
  
  <p>Anyway in my application controller:</p>
  
  <pre><code>unless Rails.application.config.consider_all_requests_local
    rescue_from Exception, :with =&gt; :render_error
    rescue_from ActionController::RoutingError, ActionController::UnknownController,      ::AbstractController::ActionNotFound, ActiveRecord::RecordNotFound, :with =&gt;    :render_error_not_found
  end
  </code></pre>
  
  <p>Then the render error method:</p>
  
  <pre><code>def render_error(exception)
    notify_airbrake(exception)
    Rails.logger.fatal exception
    Rails.logger.fatal exception.backtrace.join("\n")
    respond_to do |format|
      format.html { render :template =&gt; "errors/error_500", :layout =&gt; 'layouts/application'}
      format.all { render :nothing =&gt; true, :status =&gt; 500 }
    end
  end
  </code></pre>
  
  <p>It seems that now my logs are being filled with a much longer then usual backtrace.
  Why is that happening? Is there a way to show just the "important" part of a backtrace?
  And is it correct to call airbrake here?</p>
  
  <p>Thanks</p>