Concatenate results of a single column query

Hi All,
I would like to concatenate results of a single column query using
PostgreSQL 7.3.

Something like the coming feature

SELECT
p.name, ARRAY(SELECT nicknames FROM people WHERE people.id = p.id)
FROM people AS p

(devel docs for 7.5:
http://developer.postgresql.org/docs/postgres/sql-expressions.html )

Any suggestions?

Thanks
Marco