In Web Access I want to proxy to 2 separate mailboxes with the same account name but different domains. We host different companies on our e-mail system and they want the same account names like,

After setting this up and granting proxy access, go to Web access, Proxy button and type in the name "customerservice" it fills in, arrow down it correctly shows me the second but when I hit the Login button it always logs me into It will never allow me to login to the second account even if I type in I have to type in Big pain for our users.