BUG #6712: PostgreSQL 9.2 beta2: alter table drop constraint does not work on inherited master table

The following bug has been logged on the website:

Bug reference:      6712
Logged by:          Miroslav =C5=A0ulc
Email address:      miroslav.sulc@fordfrog.com
PostgreSQL version: Unsupported/Unknown
Operating system:   Gentoo Linux
Description:=20=20=20=20=20=20=20=20

here is the test case:

test=3D# create table test_constraints (id int, val1 varchar, val2 int, uni=
que
(val1, val2));
NOTICE:  CREATE TABLE / UNIQUE will create implicit index
"test_constraints_val1_val2_key" for table "test_constraints"
CREATE TABLE
test=3D# create table test_constraints_inh () inherits (test_constraints);
CREATE TABLE
test=3D# alter table only test_constraints drop constraint
test_constraints_val1_val2_key;
ERROR:  constraint "test_constraints_val1_val2_key" of relation
"test_constraints_inh" does not exist


postgresql tries to drop the constraint even from descendant table though
"only" is specified.