Custom recipients have a distinguished name that is of local significance only; therefore the distinguished name of a custom recipient is always ignored when searching the GWART for the recipient. Although the custom recipient's distinguished name and primary X.400 proxy O/R address are contained in the P1 recipient address, they are not used in the routing process. Instead, routing is accomplished through the Target Address attribute of the custom recipient.
During routing only, an X.400 target address overrides a standard O/R address and route. A non-X.400 target address overrides the DDA portion of an O/R address and routes the message using the DDA attributes found in the GWART. The target address does not overwrite the O/R address in the P1 header of the message. If the target address is not specified in the message, it is created from the X.400 proxy address found by reading the distinguished name, as for mailboxes.
If no target address is found for the custom recipient, the primary X.400 proxy O/R address (if any) is used for routing.