SQL/MED compatible connection manager

Howdy,

Currently pl/proxy, dblink, DBI-link etc. each have their own remote connection
info management infrastructure (or none at all). It would certainly help if
they could use a common connection database -- with access control, pg_dump
support, etc. There have been hints that a SQL/MED compatible connection
manager would be desirable:
http://archives.postgresql.org/pgsql-hackers/2008-09/msg00314.php
http://archives.postgresql.org/pgsql-hackers/2008-09/msg00909.php

So the proposal is to implement a small subset of SQL/MED to cope with
connection info management -- connection manager. This will only manage the
connection metadata and provide the required system catalogs and commands for
maintaining them. The actual connection management (open/close etc.) is still
handled by the client modules.

I have put together a draft that describes a possible implementation:
http://wiki.postgresql.org/wiki/SqlMedConnectionManager

Tons of details have been omitted, but should be enough to start discussion.
What do you think, does this sound usable? Suggestions, objections?

thanks,
Martin