foreign key from array element

Hello the list,

recently I'm cooking a database for an application, that I feel is best
implemented with tables containing arrays.

I have found some related info here:
http://archives.postgresql.org/pgsql-hackers/2008-09/msg01356.php

although the initial advice in that thread was: not to use arrays and:
"learning database best practice".

the thread eventually went into accepting this for implementation:
http://archives.postgresql.org/pgsql-hackers/2008-09/msg01341.php

Does anyone know if the implementation actually happened since? In which
version? How does the syntax loook like?

-R