javascript 下拉框关联时的数组问题

在用javascript做客户端的，下拉框关联时，关联数据库的表超过三千条（行），就出现错误提示。
个人怀疑是数组长度的上限所至，请各位高手指教！
代码如下：
<script language = "JavaScript">
<%
'打开专业表，第二层
dim rs,sql,count,rs1,sql1
sql = "select * from district order by locationid asc"
set rs = conn.execute(sql)
%>
//第二层，数组表
var onecount;
onecount=0;
subcat = new Array();
<%
count = 0
do while not rs.eof
%>
subcat[<%=count%>] = new Array("<%= trim(rs("districtname"))%>","<%= trim(rs("locationid"))%>","<%= trim(rs("districtid"))%>");
<%
count = count + 1
rs.movenext
loop
rs.close
set rs=nothing
%>
onecount=<%=count%>;
//获得第二层选项
function changelocation(locationid)
{
document.myform.smalllocation.length = 0;
var locationid=locationid;
var i;
document.myform.smalllocation.options[0] = new Option('====所有地区====','0');
for (i=0;i < onecount; i++)
{
if (subcat[i][1] == locationid)
{
document.myform.smalllocation.options[document.myform.sm