CKEditor within an iFrame

I ma running CKEditor within an iFrame and the editor will load, but will not load the data that it should load when called. I have the editor working fine of it is not contained within the iFrame. Here is the code used to call the editor:

<?php
$myFile = $_POST['editfile'];
//$myFile = "maincontent.inc";
$fh = fopen($myFile, 'r');
$theData = fread($fh, filesize($myFile));
fclose($fh);
?>

   <form method="post" action="dumpeditfile.php?editfile=<?php echo $myFile;?>">
      <p>
         <textarea id="editor1" name="editor1"><?php echo $theData;?></textarea>
         <script type="text/javascript">
            CKEDITOR.replace( 'editor1');
         </script>
      </p>
   </form>

Any ideas?