为何JAVASCRIPT一打开页面调用模态对话框错误提示说对话框不支持属性或方法

[hzdtf]

function SelectOrgGroup(exec,div1,div2,OrgIDS,GroupIDS,ORG_GROUP_IDS)
{
//exec 代表打开窗口是否自动关闭,close表示自动关闭
//div1(div2) 要显示部门(群组)的标签ID 注:非控件ID
//OrgIDS(GroupIDS) 选择的部门(群组)ID
//ORG_GROUP_IDS 部门加群组ID值组合
//alert(document.getElementById(div1).innerHTML);
//alert(document.getElementById(div2).innerHTML);
//alert(document.getElementById(OrgIDS).value);
///alert(document.getElementById(GroupIDS).value);
//alert(document.getElementById(ORG_GROUP_IDS).value);
var url=g_RootDirectory+"PlugIns/DefineObject/SessionOrgGroupIDS.aspx?ts="+Math.random();
var value="OrgGroupIDS="+escape(document.getElementById(ORG_GROUP_IDS).value);
var reValue=cex_XmlHttpRequestPost(url,value);

var PageUrl = g_RootDirectory+'PlugIns/DefineObject/SelectOrgGroup.aspx?ts=' + Math.random();
var o = new Object();
o.parentWindow = window;
o.exec=exec;
if(exec=="close")
var strFeatures = "dialogWidth=0px;dialogHeight=0px;center=yes;help=no;status=no;";
else
var strFeatures = "dialogWidth=408px;dialogHeight=448px;center=yes;help=no;status=no;";

arReturn = window.showModalDialog( PageUrl, o, strFeatures);

if(arReturn!=undefined)
{
if(arReturn=='')
{
//alert(document.getElementById(ORG_GROUP_IDS).value);

document.getElementById(div1).innerHTML='';
document.getElementById(div2).innerHTML='';

document.getElementById(OrgIDS).value='';
document.getElementById(GroupIDS).value='';
document.getElementById(ORG_GROUP_IDS).value='';
}
else
{
var orgNames='',groupNames='';
var returns=arReturn.split(Split);
var orgIDS='';
var groupIDS='';
var oRG_GROUP_IDS='';
for(var i=0;i<returns.length;i++)
{
var childReturns=returns[i].split(Split2);
var childName=childReturns[1].substring(childReturns[1].indexOf("：")+1);

if(oRG_GROUP_IDS=='')
oRG_GROUP_IDS="'"+childReturns[0]+"'";
else
oRG_GROUP_IDS+=",'"+childReturns[0]+"'";

if(childReturns[0].charAt(0)=='O')
{
if(orgIDS=='')
orgIDS=childReturns[0].substring(childReturns[0].indexOf('O')+1);
else
orgIDS+=','+childReturns[0].substring(childReturns[0].indexOf('O')+1);

if(orgNames=='')
orgNames=childName;
else
orgNames+="<BR>"+childName;
}
else
{
if(groupIDS=='')
groupIDS=childReturns[0].substring(childReturns[0].indexOf('G')+1);
else
groupIDS+=','+childReturns[0].substring(childReturns[0].indexOf('G')+1);

if(groupNames=='')
groupNames=childName;
else
groupNames+="<BR>"+childName;
}
}
document.getElementById(OrgIDS).value=orgIDS;
document.getElementById(GroupIDS).value=groupIDS;
document.getElementById(ORG_GROUP_IDS).value=oRG_GROUP_IDS;

document.getElementById(div1).innerHTML=orgNames;
document.getElementById(div2).innerHTML=groupNames;
}
}

var url=g_RootDirectory+"PlugIns/DefineObject/SessionOrgGroupIDS.aspx?&ts="+Math.random();
var value="OrgGroupIDS=";
var reValue=cex_XmlHttpRequestPost(url,value);

}


如上代码,,一打开页面就在调用该函数,出现脚本错误:对话框不支持属性或方法,错误代码是arReturn = window.showModalDialog( PageUrl, o, strFeatures);
有些电脑打开就没有问题,有些有问题,,这到底是怎么回事?请各位高手赐教