Why the error of out of range at large return

[cschang]

Error: "ORA-06513: PL/SQL: index for PL/SQL table out of range for host language array ORA-06512: at line 1
/vd2/asp/BinInactivityResults.asp, line 249"

the error only appeared when I had a large number records return (> 12000), anything less 7000 is fine (I had not tried any number between). Wonder why? I am using oracle 8.1.7, retrun table type reocrds with my IIS 4 on NT 4

'ASP sysntax as
...
set commBinAct = server.CreateObject ("ADODB.Command")
commBinAct.ActiveConnection = connBinAct
commBinAct.CommandText = pkgcall
commBinAct.CommandType = adCmdText
commBinAct.Parameters.Refresh
' .. other command object parameters

set rsBinAct = server.CreateObject ("ADODB.Recordset")
rsBinAct.CursorLocation = adUseClient
rsBinAct.Open commBinAct

....
l_rowcount = rsBinAct.Fields("o_rowcount")
....

'display the recordset in HTML table

Do While NOT rsBinAct.EOF
..

Loop

' to regain the all records for other use
IF cint(l_rowcount) > 0 Then
commBinAct.Parameters(5) = 1
commBinAct.Parameters(6) = cint(l_rowcount)
rsBinAct.Close
rsBinAct.Open commBinAct ' <--- line 249
Session("InactiveBIN") = rsBinAct.GetRows
End If

set commBinAct = Nothing
rsBinAct.Close
set rsBinAct = Nothing
connBinAct.Close
set connBinAct = Nothing