В Лисе работает. На таком наборе:
<script type="text/javascript">
<!--
function chsz(xobj, id, w, h, speed){
var t1, t2;
var obj=document.getElementById(id);
var n=x=Number(obj.offsetWidth), m=y=Number(obj.offsetHeight);
t1 = setInterval(function(){
if(n<w){
n+=5;
obj.style.width=n+'px'
}
if(m<h){
m+=5;
obj.style.height=m+'px'
}
if(n>=w&&m>=h){
clearInterval(t1)
}
}, speed);
xobj.onmouseover=function(){
clearInterval(t2);
t2=null;
if (!t1) t1 = setInterval(function(){
if(n<w){
n+=5;
obj.style.width=n+'px'
}
if(m<h){
m+=5;
obj.style.height=m+'px'
}
if(n>=w&&m>=h) clearInterval(t1)
}, speed);
};
xobj.onmouseout=function (){
clearInterval(t1);
t1=null;
if (!t2) t2=setInterval(function(){
if(n>x){
n-=5;
obj.style.width=n+'px'
}
if(m>y){
m-=5;
obj.style.height=m+'px'
}
if(n<=x&&m<=y) clearInterval(t2)
}, speed);
};
return
}
-->
</script>
</head>
<body>
<table><tr>
<td id="libcell" style="border:1px solid red" onmouseover="chsz(this,'descrlib','100','100','1') ">..........</td></tr></table>
<div id="descrlib" style="width:10px;height:10px;border:1px solid green"></div>
</body>
</html>