title: Flex Advance datagrid date column sorting problem
body: <p>I'm trying to sort <code>ArrayCollection</code> with following dates, and getting unexpected results.</p>
  
  <pre><code>14-Apr-1980
  01-Feb-1975
  30-Dec-1977
  27-Oct-1968
  </code></pre>
  
  <p>I'm using following code to sort,</p>
  
  <pre><code>private function sortDate(obj1:Object, obj2:Object):int
  {
      var d1:Number = (new Date(Date.parse(obj1.date))).getTime();
      var d2:Number = (new Date(Date.parse(obj2.date))).getTime();
      if(d1 &lt; d2) 
      {
          return -1;
      } 
      else if(d1 == d2) 
      {
          return 0;
      }
      return 1;
  }
  </code></pre>
  
  <p>And it's called like ,</p>
  
  <pre><code>&lt;mx:AdvancedDataGridColumn dataField="dob"
  headerText="Date of birth:"
  sortCompareFunction="sortDate"
  dataTipFunction="dateFormat" /&gt;
  &lt;/mx:columns&gt;
  </code></pre>
  
  <p>Results are coming like ,</p>
  
  <pre><code>27-Oct-1968
  01-Feb-1975
  14-Apr-1980
  30-Dec-1977
  </code></pre>
  
  <p>What am I missing ?</p>
  
  <p>(Note : my date format in <code>AdvancedDataGrid</code> is <code>DD-MMM-YYYY</code> )</p>