Its bit difficult to explain but very simple problem.
We have internal sendmail server and hosted server. Both are set to same domain name. We have mixed mail accounts.
For example we have two user in one office. email@example.com is local only firstname.lastname@example.org is internal plus external.
Internal means we create user on local linux box where sendmail is set.
External means we create user on local and hosted server.
email@example.com can send mails to any internal user created on Linux box where sendmail is installed. But he can not send mail to outside domain and no mail can be sent to him as there is no account created on external hosted server.
firstname.lastname@example.org can send mails to internal as well as all other domains through sendmail's smart_host feature, which uses hosted server's smtp. email@example.com can get all external emails internally through Fetchmail on linux box.
Now we have third user firstname.lastname@example.org who will be always outstation and can use external server only.
So I can not create account on local linux box for email@example.com because his mail will get delivered locally only. I don't want to create alias and send his mails to gmail or yahoo's account. I want to send emails to his external account from any internal user.
How this can be done? Thanks in advance.