title: iOS Code Signing Fails Only For Jenkins
body: <p>I'm trying to build a Xamarin Touch project from a Jenkins build it fails at the code signing phase.</p>
  
  <p>My certificates and keys are in the System keychain so should be accessible to Jenkins. I have no code signing issues when I build the project:</p>
  
  <ul>
  <li>Using Xamarin Studio.</li>
  <li>Using <code>/bin/bash</code> and <code>xbuild</code> logged in as the Jenkins user.</li>
  <li>Using <code>/bin/sh</code> and <code>xbuild</code> logged in as the Jenkins user.</li>
  </ul>
  
  <p>The only time the code signing issue is seen is when the Jenkins build itself.</p>
  
  <p>The error is "User interaction is not allowed", I'm at a loss as to explain what is going wrong for the Jenkins build when everything is working as the Jenkins user when I run the same command from a shell.</p>