Froxlor/templates/Classic/misc/htmlarrowcode.tpl

<a href="{$baseurl}&amp;sortfield={$fieldname}&amp;sortorder=desc">
	<img src="images/Classic/order_desc.gif" border="0" alt="" />
</a>
<a href="{$baseurl}&amp;sortfield={$fieldname}&amp;sortorder=asc">
	<img src="images/Classic/order_asc.gif" border="0" alt="" />
</a>