Weird prepared stmt behavior

Hackers,

Is this expected?  If so, why?  I'd expect the prepared stmt to be
deallocated.

alvherre=# begin;
BEGIN
alvherre=# prepare tres as select 3;
PREPARE
alvherre=# rollback;
ROLLBACK
alvherre=# execute tres;?column? 
----------       3
(1 fila)


-- 
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
FOO MANE PADME HUM