X.400 messages can be directed to the PMDF-X400 gateway from local users as well as remote mail systems. Messages can include any combination of X.400 and non-X4.00 recipients. X.400 recipients are indicated to PMDF by addresses of the form:

X.400-OR-name@X.400-gateway-domain

For example, in the address

/g=Fred/s=Smith/prmd=example/admd=telemail/c=us/@x400.example.com

/g=Fred/s=Smith/prmd=example/admd=telemail/c=us/ comprises the X.400-OR-name part of the address, and x400.example.com comprises the X.400-gateway-domain part of the address.