Version: pgAdmin III 0.8.0 Devel (Jul 30 2003)
Steps:
1) open pgAdmin III, go to arbitrary table and select its constraints
2) add new constraint with empty name (i.e. leave field Name empty)
Result: added constraint is not shown in list of constraints and you have to
refresh constraints tree node to show it. If added constraint has a name,
then this problem does not occur.
Regards,
Matej Rizman