BUG #3661: Missing equality comparator: string = integer

The following bug has been logged online:

Bug reference:      3661
Logged by:          David Bachmann
Email address:      david.bachmann@ersystems.ch
PostgreSQL version: 8.3-beta1
Operating system:   Windows XP
Description:        Missing equality comparator: string = integer
Details:

This does not function any more under PG 8.3-beta1:

select '5'::varchar = 5;
ERROR:  operator does not exist: character varying = integer

select '5'::char = 5;
ERROR:  operator does not exist: character = integer


Note that this still works:
select '5' = 5;