user@magnus.acs.ohio-state.eduSimply specifying
user@magnuswill not suffice because this is expanded to the address
user@cis.ohio-state.eduThe address user@magnus is expanded to user@cis.ohio-state.edu because it does not provide enough information to indicate that "magnus" refers to an address which is not local to the CIS department. This default action is taken whenever a hostname without a subdomain is given. This conversion is done so that mail addresses such as fine@soccer will go to the right place.
In our nameserver (local data base of host names) magnus is translated to magnus.acs.ohio-state.edu. However, the mail system doesn't use the nameserver at that level, so it can't access this information.
Note that it is useful to create an alias when the full address must be specified as in this instance.
See also man mail, man elm, or the elm user's guide.
Last Update: 1/10/94 JGW