Dandello 8 Posting Whiz in Training

This:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="$abbr_lang" lang="$abbr_lang">
<head>
    <title>$linktitle</title>
    <meta http-equiv="Content-Type" content="text/html; charset=$yymycharset" />
    <link rel="stylesheet" href="$yyhtml_root/Templates/Forum/$usestyle.css" type="text/css" />
    <script type="text/javascript">
        function insertHyperlink() {
            window.opener.document.getElementById('wysmessage').contentWindow.focus();
            var theLinktype = '$linkttext';
            var mylink = document.getElementById('url').value;
            var theLink = theLinktype + mylink;
            window.opener.document.getElementById('wysmessage').contentWindow.document.execCommand("Unlink", false, null);
            window.opener.document.getElementById('wysmessage').contentWindow.document.execCommand("CreateLink", false, theLink);
            window.close();
        }
    </script>
</head>
<body class="windowbg" style="min-width: 460px; margin: 0px; padding: 0px;">
    <form>
    <table class="tabtitle">
        <tr>
            <td>
                &nbsp;<img src='$modimgurl/chatce/chat1.png' alt="$chatce_txt{'chatbox'}" style="vertical-align: middle; margin-bottom: 1px;" /> <b>$linktitle</b>
            </td>
        </tr><tr>
            <td class="windowbg small" id="mlform" style="width: 100%; text-align: center; margin-left: auto; margin-right: auto; margin-top: 3px; margin-bottom: 3px; padding: 3px;">
                <b>$linkttext</b> <input type="text" class="small" size="55" id="url" name="url" style="width: 300px; vertical-align: middle;" /> <img src="$modimgurl/chatce/linkok.gif" alt="$editor_txt{'insert'}" title="$editor_txt{'insert'}" style="cursor: pointer; vertical-align: middle;" onclick="insertHyperlink();" /><img src="$modimgurl/chatce/linkcl.gif" alt="$editor_txt{'cancel'}" title="$editor_txt{'cancel'}" style="cursor: pointer; vertical-align: middle;" onclick="window.close();" />
             </td>
        </tr>
    </table>
    </form>
    <script type="text/javascript">
        document.getElementById('url').focus();
    </script>
</body>
</html>

Chrome and Safari properly insert the url that's put into the input box into the iframe with the id of 'wysmessage' in the parent html page. FireFox and MSIE do not. So far I have tried using setTimeout to delay the focus for MSIE but that didn't help.
To complicate matters there are other input windows that don't use the input tag to create an input box (these are color picker windows) and they work fine in FireFoax and MSIE.