Just successfully implemented this mod for 4.4.4, worked like a charm. Thanks Alex
I did have to implement the extra step in post #26
http://forum.x-cart.com/showpost.php?p=333175&postcount=26
Additionally I modified /common_files/mail/html/order_invoice.tpl
to include an if statement to check if there is a saved value for the field :
{foreach from=$order.extra.additional_fields.address.B item=v}
{if $v.value ne ""}
<tr>
<td><strong>{$v.title}:</strong></td>
<td>{$v.value}</td>
</tr>
{/if}
{/foreach}
Has to be done for the billing and shipping fields both. Just keeps it from displaying the field title unless the user has a value saved for that field.