Catalogs design question

Hello all!!

I'm developer of a interface for PostgreSQL for the Borland Kylix
and Delphi tools (http://www.vitavoom.com) I've run into the following
problems with catalogs:

- pg_group: the grolist field is an array. How can I make a query
that tell me the usernames of a group ?
- pg_proc: the proargtypes field is an array. How can I make a query
that will link those types to the pg_types catalog ???

This catalog design seems a very crude hack to make the things
working for me. Can't those relations be separated in another table ? Or
maybe a function that can search for a value in array, and make a wroking
reference for an array
element in a relation (something like "select typname from pg_type, pg_group
where oid
in grolist").
I also quote the PotgreSQL user manual
(http://www.ca.postgresql.org/users-lounge/docs/7.1/postgres/arrays.html)

"Tip: Arrays are not lists; using arrays in the manner described in the
previous paragraph is often a sign of database misdesign. The array field
should generally be split off into a separate table. Tables can obviously be
searched easily."

Best Regards,
Steve Howe