postgres not use table access permissions ?

Hi,

I start yesterday CVS PostgreSQL server, and saw strange thing:
from user postgres:
# create database test;
CREATE
# \c test;
#create user bobson with password '1' nocreatedb nocreateuser;
CREATE
#create table a (a int4);
CREATE
#revoke all on a from public;
CHANGE

and now from user bobson after conecting to test database:
#insert into a values ('1');
INSERT 19104 1

hmmm... looks like bug. Or I miss something?

so next from user postgres:
#revoke all on a from bobson;
CHANGE

and from user bobson after connect:
#delete from a;
DELETE 1

Postgres ignore access permissions ?
BTW... in my pg_hba.conf
local            password
...

regards
Robert 'BoBsoN' Partyka