title: How do I access external functions in a class using GroovyScript
body: <p>I have a simple script like this...</p>
  
  <pre><code>def createEntry(service){
      ...
  }
  class Service {
      ...
      void create(){
          createEntry(this)
      }
  }
  </code></pre>
  
  <p>But when I run this code I get the following...</p>
  
  <blockquote>
    <p>hudson.remoting.ProxyException: groovy.lang.MissingMethodException: No signature of method: Service.createEntry() is applicable for argument types: (Service) values: [Service@64bbfb0d]</p>
  </blockquote>