Named constraints

I am trying to create a named constraint, but it doesn't seem to take the
name.

I got an example from the referential integrity page
http://techdocs.postgresql.org/techdocs/hackingreferentialintegrity.php

After looking the examples I created SQL script

create table Users
(
UserID serial primary key,
GroupID integer
constraint fkgroup
references Groups,
LocationID integer
constraint fklocations
references Locations,
Password varchar(20) NOT NULL,
Name varchar(16) NOT NULL,
LongName varchar(20) NOT NULL,
Email varchar(50)
);

It creates the table, but lists the triggers
Triggers: RI_ConstraintTrigger_13682386,
RI_ConstraintTrigger_13682392

Is there a different syntax I should be using?