Database Comments

Hi,

Using COMMENT ON DATABASE only allows you to create a comment
for your current database which is then only visible from that database.
However, if I manually insert appropriate values into pg_description
in other databases I can make comments appear for another database.

e.g. If some users have access to databases A,B&C, I can insert
values so that the users can see descriptions for each database
from any of them.

Is it safe to do this, or can it have unexpected side effects?

Also is there any intention to have a 'COMMENT ON [ROLE|USER|GROUP]'
facility. It would be quite useful to be able to do something like

COMMENT ON USER jbloggs IS 'Joe Bloggs <j(dot)bloggs(at)foo(dot)bar>'

-Mark