try
HTML Code:
<td>
<if condition="!is_member_of($bbuserinfo,array(2,4,5,6,7))">
You must be registered to use the shoutbox
<else />
<iframe frameborder="0" width="100%" height="50" src="http://cbox.co.za/box/?boxid=439&boxtag=7868&sec=form&wname=68&wemail=68&wmsg=175" marginheight="0" marginwidth="0" scrolling="no" name="cboxform" allowtransparency="yes" style="border: #ababab 0px solid; border-top: 0px;"></iframe>
</if>
</td>
make sure you are using a vbulletin shoutbox, cuz this is only for it. As I saw in your site it's not a vbulletin hack