title: Mule AMQP connector: Value is not facet-valid with respect to enumeration
body: <p>I'm trying to read a property from a configuration file (.properties) in Mule but it seems not to take the value from it.</p>
  
  <p>These are my configuration and properties files:</p>
  
  <h3>dev.properties File</h3>
  
  <pre><code>amqp.host=localhost
  amqp.port=5672
  amqp.username=guest
  amqp.password=guest
  amqp.ackMode=MANUAL
  amqp.prefetchCount=1
  </code></pre>
  
  <h3>XML Configuration File</h3>
  
  <pre><code>&lt;context:property-placeholder location="dev.properties"/&gt;
  
  &lt;amqp:connector 
      name="amqpLocalhostConnector"
      host="${amqp.host}"
      port="${amqp.port}"
      username="${amqp.username}"
      password="${amqp.password}"
      ackMode="${amqp.ackMode}"
      prefetchCount="${amqp.prefetchCount}" /&gt;
  </code></pre>
  
  <p>When I execute the application, it throws the following error:</p>
  
  <pre><code>ERROR 2015-06-29 12:04:33,540 [main]
  org.mule.module.launcher.application.DefaultMuleApplication: null
  org.xml.sax.SAXParseException: cvc-enumeration-valid: Value '${amqp.ackMode}' is not
  facet-valid with respect to enumeration '[AMQP_AUTO, MULE_AUTO, MANUAL]'.
  It must be a value from the enumeration.
  </code></pre>
  
  <p>If I set the property like this:</p>
  
  <pre><code>    ackMode="MANUAL"
  </code></pre>
  
  <p>the application runs without a problem.</p>
  
  <p>How can I get this to work? Thanks.</p>