IE6 图片轮换效果JS报类不能支持automation操作

Question

function cleanallstyle() {
    for (i=0;i<7;i++) {
document.getElementById("focus_"+i).className = "" ;
    }
}
function show_focus_image(index) {
             clearTimeout(refreshHotQueryTimer);
    setHotQueryList(index);
    refreshHotQueryTimer = setTimeout('refreshHotQuery();', 5000);
}
function setClick() {
    clearTimeout(refreshHotQueryTimer);
         }
var refreshHotQueryTimer = null ;
var hot_query_td =  document.getElementById('HotSearchList');
setHotQueryList(CurrentHotScreen);
refreshHotQueryTimer = setTimeout('refreshHotQuery();', 5000);调用<a  onmouseover="show_focus_image(" + j + ")" href="#target="_blank" blockid="931">文字</a>在IE6下报类不能支持automation操作，求解释