Add an entry in the user file like this:
daveuucp Password = "secret"
User-Service-Type = Login-User,
Login-Service = Rlogin,
Login-Host = uucp.mydomain.com,
Login-TCP-Port = 513
This will rlogin them to your UUCP host. You could also change the login
service and port to connect them to uucp directly, if you support the
uucp over tcp/ip protocol...