Normally, the $j macro is automatically defined to be your
fully qualified domain name (FQDN). Sendmail does this by getting your host
name using gethostname and then calling
gethostbyname on the result. For example, in some environments
gethostname returns only the root of the host name (such as
"foo"); gethostbyname is supposed to return the FQDN
("foo.bar.com"). In some (fairly rare) cases, gethostbyname may
fail to return the FQDN. In this case you MUST define
confDOMAIN_NAME to be
your fully qualified domain name. This is usually done using:
Dmbar.com define(`confDOMAIN_NAME', `$w.$m')dnl