table.tablesorter .header,
table.tablesorter .tablesorter-header {
	background-repeat: no-repeat;
	background-position: center right; 
	cursor: pointer;
}
table.tablesorter th.headerSortUp,
table.tablesorter th.tablesorter-headerSortUp {
	background-image: url(asc.gif);
}
table.tablesorter th.headerSortDown,
table.tablesorter th.tablesorter-headerSortDown {
	background-image: url(desc.gif);
}