Need to check disabled constraints

Hi,

Can anyone please let me know how I can check disabled constraints in
postgresql 9.1 database.
I know that ALTER TABLE tablename DISABLE TRIGGER ALL; can disable foriegn
constraints, but how I can check if it is really disabled. Similarly I need
to check if constraint is enable.

In oracle we have option to check status of constraint in user_constraints
table but do we have same in postgresql as well?

Appreciate your response.

Thanks.