addressing summary

Personally my preference would be to define that capability for ANONYMOUS-RELAY.
That is any container which provides this capability is declaring that it supports the establishment of incoming links from other containers to itself, where the target of the link has the empty address, and the sending of a message with "to" property "X" on such a link will route said message within the container in the same way sending the message on a link established to the target with address "X".
This says nothing about routing between containers or the support of "global" addresses.

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Rob Legally required information for business correspondence/Gesetzliche Pflichtangaben für Geschäftskorrespondenz: http://www.jpmorgan.com/pages/international/germany/email