[shan]

Here you go,

clever little trick that. I did this for V3.5.3 but youll see the idea of how it works for any other version.

This is the code for the zip code part of the registration form

<tr valign=middle>
<td align=right>{$lng.lbl_zip_code}</td>
<td><font class=Star>*</font></td>
<td nowrap>
<input type=text name=b_zipcode size=32 maxlength=32 value="{$userinfo.b_zipcode}" onKeyUp="this.value=this.value.toUpperCase()" onChange="check_zip_code()" >
{if $reg_error ne "" and $userinfo.b_zipcode eq ""}<font class=Star>&lt;&lt;</font>{/if}
</td>
</tr>