COMMUTATOR doesn't seem to work

Maybe I am using it wrong but I get no error message when I use it. I
have a type called chkpass (a version is in the additional supplied
modules) and I create the equality operator like this:

CREATE OPERATOR = (
PROCEDURE = eq,
LEFTARG = chkpass,
RIGHTARG = text,
COMMUTATOR = =,
NEGATOR = <>
);

This works;

cosmostest=# SELECT 'aaa'::chkpass = 'aaa';
?column?
----------
t
(1 row)

But...

cosmostest=# SELECT 'aaa' = 'aaa'::chkpass;
ERROR: operator is only a shell: text = chkpass
LINE 1: SELECT 'aaa' = 'aaa'::chkpass;

When I look at the operators I see why, sort of...

public | = | chkpass | text | boolean |
public | = | text | chkpass | - |

So while it created the operator it didn't set a return type.

I don't know if this is a new issue or I simply got lucky and never
tried the opposite test before but I see this in 9.0.4 and 9.1.3.
Am I using the command improperly?

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D'Arcy J.M. Cain <darcy(at)druid(dot)net> | Democracy is three wolves
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