var $test_focus;
var $focus_prev = new Array();
function focus_input(input_id){	
	$test_focus = "already" + input_id;
	if ($focus_prev[input_id] != $test_focus) {
		document.getElementById(input_id).value = '';
	}
	$focus_prev[input_id] = "already" + input_id;
}