BUG #5755: Query Optimzer Bug

The following bug has been logged online:

Bug reference:      5755
Logged by:          Elliott Groszek
Email address:      elliott.groszek@navy.mil
PostgreSQL version: 8.4.4
Operating system:   RedHat
Description:        Query Optimzer Bug
Details:

The following SQL statements produce different query plans even though
"phone" is not reference in the SQL!

explain update customer set login_name =
(select "NESSOuserName" from person,phone
where person.cac_cert=customer.cac_cert);


explain update customer set login_name =
(select "NESSOuserName" from person
where person.cac_cert=customer.cac_cert);

Please advise,  Elliott