title: Spring Security 3: @PostFilter not working
body: <p>Hi
  I am new to Spring Security 3 and was trying out @PostFilter on a method declared in an Interface but the returned Collection is not getting filtered. </p>
  
  <p>Here is the code:</p>
  
  <pre><code>public interface IProductService {
  
   @PostFilter("(!filterObject.customersOnly) or (filterObject.customersOnly and hasRole('ROLE_USER'))")
   Collection&lt;Category&gt; getCategories();
  }
  </code></pre>
  
  <p>customerOnly is a boolean attribute in a domain object Category.</p>
  
  <p>I've added the following element on xyz-security.xml:</p>
  
  <pre><code>&lt;global-method-security pre-post-annotations="enabled" /&gt;
  </code></pre>
  
  <p>Could someone help me understand what am i missing?</p>
  
  <p>Thanks</p>