问一个比较奇怪的问题

[moplusplus]

我的代码如下:
<DIV id=demo000
style="FLOAT: right; OVERFLOW: hidden; WIDTH: 301px; MARGIN-RIGHT: 0px; HEIGHT: 19px">
<DIV id=demo111 style="LINE-HEIGHT: 19px; height: 19;">
<TABLE cellSpacing=0 cellPadding=0 width="100%" height="19">
<TBODY>
<tr>aaa</tr>
<tr>bbb</tr>
<tr>ccc</tr>
</TBODY></TABLE></DIV>
<DIV id=demo222></DIV></DIV>
<SCRIPT>
<!--
var speed = 25;//滚动速度
var rows = 19;//每行高度
var stim = 125; //停留时间倍数 * speed
var stop = 0; //初始化值，不管
demo222.innerHTML = demo111.innerHTML
function Marquee999(){
if(demo000.scrollTop%rows==0 && stop<=stim){
stop++;
return;
}
stop = 0;
if(demo222.offsetTop-demo000.scrollTop<=0)
demo000.scrollTop-=demo111.offsetHeight
else{
demo000.scrollTop++
}
}
var MyMar999 = setInterval(Marquee999,speed)
demo000.onmouseover = function() {clearInterval(MyMar999)}
demo000.onmouseout = function() {MyMar999=setInterval(Marquee999,speed)}
-->
</SCRIPT>

当我运行以上代码时,区域滚动显示完一个循环后(即aaa bbb ccc)后,并没有立即显示下一个滚动循环的开始(即aaa) 而是显示了一块空白.请问用什么方法能去掉这个空白,让滚动字幕不停的循环显示呢?问题出在什么地方呢?

谢谢

[zl_c]

<DIV id=demo000 style="FLOAT: right; OVERFLOW: hidden; WIDTH: 301px; MARGIN-RIGHT: 0px; HEIGHT: 19px"> 
	<DIV id=demo111 style="LINE-HEIGHT: 19px;"> 
		<TABLE cellSpacing=0 cellPadding=0 border=0 width="100%"> 
			<tr><td height="19">aaa</td></tr> 
			<tr><td height="19">bbb</td></tr> 
			<tr><td height="19">ccc</td></tr> 
		</TABLE> 
	</DIV> 
	<DIV id=demo222></DIV> 
</DIV> 
<SCRIPT> 
<!-- 
  var speed  = 25;//滚动速度 
  var rows  = 19;//每行高度 
  var stim  = 125; //停留时间倍数 * speed 
  var stop  = 0; //初始化值，不管 
  demo222.innerHTML = demo111.innerHTML 
  function Marquee999(){ 
    if(demo000.scrollTop%rows==0 && stop <=stim){ 
      stop++; 
      return; 
    } 
    stop = 0; 
    if(demo222.offsetTop-demo000.scrollTop <=0) 
      demo000.scrollTop-=demo111.offsetHeight 
    else{ 
      demo000.scrollTop++ 
    } 
  } 
  var MyMar999    = setInterval(Marquee999,speed) 
  demo000.onmouseover = function() {clearInterval(MyMar999)} 
  demo000.onmouseout  = function() {MyMar999=setInterval(Marquee999,speed)} 
--> 
</SCRIPT>