关于IE打印设置的问题！！！！(100分)

<object id="factory" style="display:none" viewastext classid="clsid:1663ed61-23eb-11d2-b92f-008048fdd814"
codebase="ScriptX.cab#Version=5,60,0,360"></object>
<SCRIPT LANGUAGE=javascript>
<!--
function window.onload()
{
factory.printing.paperSize = "A4" //这里有错，不知为什么？？？
factory.printing.header = "";
factory.printing.footer = "";
factory.printing.leftMargin = 10;
factory.printing.topMargin = 7;
factory.printing.rightMargin = 50;
factory.printing.bottomMargin = 5;
//factory.printing.printBackground=true;
//factory.printing.paperSize = "US Std Fanfold"

idPrint1.disabled = false;
// enable UI button
idPrint2.disabled = false;
idPrint3.disabled = false;
idPrint4.disabled = false;

}
//-->
</SCRIPT>