[VBA EXCEL] Application.Close doesn't work with asp.net

[mister.mwa]

Hello,

The following testing code will be executed without an error with
windows server 2003 and asp.net. However Excel will remain in the
process list until i kill the process or reboot the computer.

<script language='vb' runat='server'>

Private Sub Page_Load()
Dim excelApp

excelApp = CreateObject("Excel.Application")
excelApp.Quit()
excelApp = Nothing
response.write("OK")
End Sub

</script>

In asp, the excel application will be closed with the same statements,
but not in asp.net.

I have tried to add Microsoft.Excel library reference and to explicitly
declare the variables, but it didn't change anything.

I am using ws2003 with asp.net and office xp.
Anyone could tell me what to do ?

Thanks.