dhtmed.php:
Basically what I have done here is check to see if $enh has been set.
If it has, then cut out the last 6 characters of the QUERY_STRING and added '$enh=n'
Otherwise just add '&enh=n'


<?
  if($enh=="y"){
    $qLen= strlen($QUERY_STRING)-6;
    $newQuery= substr_replace($QUERY_STRING, '&enh=n', $qLen, 6);
  } else {
    $newQuery= "$QUERY_STRING&enh=n";
  }
?>

[Enter] - <? echo $lFormParagraph; ?><br>
[Shift] + [Enter] - <? echo $lFormLineBreak; ?><br>
[<a href="http://<?php echo "$SERVER_NAME$SCRIPT_NAME?$newQuery" ?>"><? echo $lFormStandardEditor; ?></a>] (<? echo $lFormStandardEditorExplain; ?>)


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form.php:
Here, since $enh will always be set, just cut out the last 6 characters and add '$enh=y'

<?php if (ereg("MSIE",$HTTP_USER_AGENT))
  $qLen= strlen($QUERY_STRING)-6;
  $newQuery= substr_replace($QUERY_STRING, '&enh=y', $qLen, 6);
  echo "&nbsp;[<a href=\"http://$SERVER_NAME$SCRIPT_NAME?$newQuery\">$lFormEnhancedEditor</a>] ($lFormEnhancedEditorExplain)";
?>