Background: I'm building an intranet based on EPiServer 7.5 and would like the users to be referenced/identified/listed in the system by their username, not DOMAIN/username.

I'm using the WindowsMembershipProvider and the WindowsRoleProvider. Looking at the standard implementation (through reflection), the provider is set to default to using just username, but this in not the case. Even when I explicitly set usernameFormat="Name" all usernames are stil set to DOMAIN/username. I can't get my head around what is happening. Am I using usernameFormat in the wrong way?

This is how it's configured:

<add name="WindowsRoleProvider"
applicationName="EPiServerSample"
type="EPiServer.Security.WindowsRoleProvider, EPiServer" />

...

<add name="WindowsMembershipProvider"
type="EPiServer.Security.WindowsMembershipProvider, EPiServer"
deletePrefix="BUILTIN\"
usernameFormat="Name" />