When you install IBM Connections Mail 1.0, having a way to diagnose how Connections sees a particular users mail setup can be very helpful - for example, which mail system (DOMINO), which mail server, which mail file, etc.
A documented method to verify this information is to use the DiscoveryServlet which is a utility that Connections Mail itself uses for that purpose.
When called, it returns full info about the mail setup for the queried users (by email address). To call it you use the following URL:
http://<hostname>/connections/resources/discovery/DiscoveryServlet?email=<email address>