bug in deferred triggers ?

Hello !

I have the following script, which (in my opinion) should not generate
an error at the final commit.

---
create table aaa_test ( id1 varchar(10), id2 int8, d date, t text,
primary key (id1, id2));
create table aab_test (idrep int8, primary key(idrep));
alter table aaa_test
add foreign key (id2)
references aab_test(idrep) match full
on delete no action on update no action deferrable;

insert into aab_test values (1);
insert into aaa_test values ('a',1);

begin work;
set constraints all deferred;
delete from aab_test where idrep=1;
insert into aab_test (idrep) values (1);
commit;
---

The deferred constraint trigger fires even if I insert the 'missing'
value 1 immediately back again into the table.

Does someone know about a workaround in the Version 7.2.1-2 I am using ?

I tried to install 7.3 on an uncritical system and there this error did
not occur - or is this behaviour a matter of configuration ?

Thanks,

Peter Schüller