Redirect http to https on OWA IIS6.0 not working

Hi,
I'm having trouble getting the redirect working on my front end server
for OWA. I've done the following

1. Installed SSL and enabled it on the default and exchange site.
2. created an asp file with the following code:
<%
If Request.ServerVariables("SERVER_PORT")=80 Then
Dim strSecureURL
strSecureURL = "https://"
strSecureURL = strSecureURL & Request.ServerVariables("SERVER_NAME")
strSecureURL = strSecureURL & "/exchange"
Response.Redirect strSecureURL
End If
%>

3. Edited the Custom Error for 403.4 so it points to the asp file when
someone puts in http and set the message type to URL.

Am i missing anything? I can't get it to redirect to https. I have
the virtual directory working, so you only have to put in
https://servername.com, but I can't get the https redirect to work
properly. I've followed numerous MS articles on this as well, and
nothing has seemed to work.