MAPI.Profile Logon With ASP

I have an ASP application that logs into Exchange server to send email. The
code looks like this:

Set objSession = CreateObject("MAPI.Session")
objSession.Logon "profileName"

strMsg = ".."
Set objMessage = objSession.Outbox.Messages.Add
objMessage.Subject = "Customer Comment"
objMessage.Text = strMsg

Set objRecip = objMessage.Recipients.Add
objRecip.Name = SendTo
objRecip.Type = 1 'CdoTo
objRecip.Resolve

objMessage.Send 'showDialog:=False
objSession.Logoff

This code worked fine when the server was WinNT / Exchange 2000, now the
server has been upgraded to Windows 2003 and Exchange 2003.

Exchange Server is running on the same machine as IIS. And the error
appears to happen when the Logon is attempted.

Any ideas as to what may have changed in Windows 2003 or Exchange 2003?