What type is required to capture the RETURNING from anUpdate?

Within 8.4, If I have an update like the following :


   EXECUTE $c$
    UPDATE field_seasons dr
        SET season_id = ds.season_id, field_id = ds.field_id
    FROM data_set ds
    WHERE ds.data_set_id = dr.data_set_id
    AND ds.season_id = _season_id
    RETURNING field_seasons_id
    $c$
   INTO _id_array;


in a pgsql FUNCTION... What is the type on the variable that can accept
the list of id's?

integer[] doesn't work.  It gives back "22P02 array value must start
with "{" or dimension information."


Roxanne