$("shopcategories_category").onchange=shopcategoriesCategoryChange;

function shopcategoriesCategoryChange()
{
var sel=$("shopcategories_category");
	if(sel.selectedIndex)
	{
	$("shopcategories_form").setAttribute("action", sel.options[sel.selectedIndex].value);
	$("shopcategories_form").submit();
	return true;
	}
return false;
}