JavaScript运行出错???

[ezerg]

具体如下:
//文件名time.js
function WriteShortYearOptions()
{
line = "";
str = "";
for (i=0; i<MAXYEARS; i++)
{
str = FIRSTYEAR + i;
line += "<OPTION value='";
line += FIRSTYEAR + i;
line += "'>";
line += str.toString().substr(2);
line += "</OPTION>";
}
return line;
}
function SetToLastWeek(varForm, Which)
{
DaysObject = eval("document." + varForm + "." + Which + "Day");
MonthObject = eval("document." + varForm + "." + Which + "Month");
YearObject = eval("document." + varForm + "." + Which + "Year");

YearObject[NowYear - FIRSTYEAR].selected = true;
MonthObject[NowMonth].selected = true;

ChangeOptionDays(varForm, Which);

DaysObject[NowDay-8].selected = true;
}

//文件名use.htm
...
<script src="time.js"></script>
...
<script language="JavaScript">
document.write(WriteShortYearOptions());
document.write(SetToLastWeek(varForm, Which));

</script>
...

1、提示错是缺少对象。
2、YearObject[NowYear - FIRSTYEAR]不是对象。

应该如何解决？？？

[ezerg]

难道没有人会吗???

[ezerg]

这和操作系统有关系吗?
我用的是IMB的aix5L