BUG: NOT boolfield kills backend

Hi, 
I just found an error in every postgres versions, 
(I tried 6.2.1, 6.3.2, and 6.4beta1 )

if I have a table with boolean field, and I want to negate that field,
it's kills the backend process... meanwhile 'select not ( 'T'::bool )'
works well...

create table t1 ( b bool );
insert into t1 values ( 'T' );

select not b from t1;
PQexec() -- Request was sent to backend, but backend closed the channel
before responding.
        This probably means the backend terminated abnormally before or
while processing the request.

	don't you have some idea what to do,?
	
	thanks, 
		Redax
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|Zsolt Varga            | tel/fax:   +36 36 422811         |
| AgriaComputer LTD     | email:     redax@agria.hu        |
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