BUG #6636: Variadic function fails with array type domain

The following bug has been logged on the website:

Bug reference:      6636
Logged by:          Lynn Dobbs
Email address:      lynn@creditlink.com
PostgreSQL version: 9.1.3
Operating system:   Linux
Description:=20=20=20=20=20=20=20=20

1. postgresql built from src.
2. The following functions on 9.0.4 but fails on 9.1.3. (Discovered during a
dump/restore for upgrade).

3. Code:
creditlink=3D# create domain foo as bigint[];
CREATE DOMAIN
creditlink=3D# create function foobar(variadic foo) as $$ select true $$
language sql;
ERROR:  42P13: VARIADIC parameter must be an array
LOCATION:  examine_parameter_list, functioncmds.c:279