Problems with Basic authentication

Problem: Why does following code in ASP work on IE4+ and NC4+, but not in a 7110:
Response.expires=-1
bstrMailbox=request.servervariables("LOGON_USER")
If Session("CURRENT_MAILBOX") <> bstrMailbox Then
Response.Buffer = TRUE
Session("CURRENT_MAILBOX")=bstrMailbox
Response.Status = ("401 Unauthorized")
Response.End
End If

It just keeps on asking the user name and password, while IE and NC do the authenication correctly. What should I do?

- Chill -