title: Grails service injection null when injected service has older grails version
body: <p>I have written a Grails Plugin, written in Grails 2.1.1, which offers a service. Now, I have created a new Grails project with Grails 2.4.4 and wanted to inject the service, but this fails.</p>
  
  <pre><code>package testproject
  
  class HomeController {
  
      def myService
  
      def index() {
          println myService
      }
  }
  </code></pre>
  
  <p>Always <code>null</code>is printed. I tested this with a Grails 2.4.4 project and with a Grail2 2.4.3 project. When I create instead my Grails Project with Grails 2.1.1 it works.</p>
  
  <p>Why? Shouldn't be a service reachable for newer versions? Do I always have to upgrade the plugin, which contains the service, to be able to use newer Grails versions?</p>