function getObj(id) {
	if (document.all) { return document.all[id]; } 
	else if(document.getElementById) {	return document.getElementById(id);	}
	else if(document.layers) { return document.layers[id]; }
}
var start = 0;
function m(step) {
	var list = getObj('l');
	if (list) {
		list = list.childNodes;
		var i = start, j = list.length;
		while (i+step < j && i < start+step) {
			list[i].style.display = 'none';
			i++;
		}
		start = i;
		var b = getObj('btn');
		if(b) b.className = (start+step >= list.length-1) ? 'e':'';
	}
	return false;
}
function f(step) {
	var list = getObj('l');
	if (list) {
		list = list.childNodes;
		var i = start-1;
		while (i >= 0 && i >= start-step) {
			list[i].style.display = 'block';
			i--;
		}
		start = i+1;
		var b = getObj('btn');
		if(b) b.className = (start == 0) ? 's':'';
	}
	return false;
}