function checkNum(obj){
	if ( obj.value ) {
		obj.value = obj.value.replace(/[^0-9]/gi , '');
		return true;
	} else {
		return false;
	}
}
var scrolling=false;
function scrollVertical(scroll,mode) {
	var div=document.getElementById(scroll);
	if (mode=='top') {
		//window.title='a'+div.scrollTop;
		if (div.scrollTop>0) {
			div.scrollTop=div.scrollTop-3;
		}
	} else {
		if (div.scrollTop+div.offsetHeight<div.scrollHeight) {
			div.scrollTop=div.scrollTop+3;
		}
	}
	if (div.scrollTop<=0) {
		div.scrollTop=0;
		document.getElementById('scroll_top_'+scroll).style.visibility='hidden';
		document.getElementById('scroll_bottom_'+scroll).style.visibility='visible';
		scrolling=false;
	} else if (div.scrollTop+div.offsetHeight>=div.scrollHeight) {
		div.scrollTop=div.scrollHeight-div.offsetHeight;
		document.getElementById('scroll_top_'+scroll).style.visibility='visible';
		document.getElementById('scroll_bottom_'+scroll).style.visibility='hidden';
		scrolling=false;
	}
	if (div.scrollTop>0) {
		document.getElementById('scroll_top_'+scroll).style.visibility='visible';
	} else if (div.scrollTop+div.offsetHeight<div.scrollHeight) {
		document.getElementById('scroll_bottom_'+scroll).style.visibility='visible';
	}
	if (scrolling) {
		setTimeout('scrollVertical(\''+scroll+'\',\''+mode+'\')',10);
	}
}

function scrollVerticalUp() {
	scrolling=false;
}