invalid input syntax for type tid: "(,)"

at a point the postgresql ODBC driver issues a command like this (not
questioning here how useful or correct it could be)

select * from table1 where ctid = '(,)';

this command works (?) returning zero rows without error, even from
psql,
when the db is hosted in the following systems:

- debian i386 using the stable postgresql7.2.1-2 package
- debian ppc using the stable postgresql7.2.1-2 package
- debian i386 using the testing postgresql7.4.2-2 package
- MacOSX 10.2 using the 7.3.4 compiled from source


but when hosted in a MacOSX 10.3 (Panther) using postgres 7.4.x
compiled from source we get:

        ERROR:  invalid input syntax for type tid: "(,)"

I've tried on three different machines and a miriad of different
configure parameters and always get the same error...

could be an incompatible version of some external lib?
who is responsible of the parsing of the command?

as hint:
when installing 7.4.2 on Panther we got a warning telling us about the
version of bison, we have upgraded it anyway to 1.875,



Pax et Bonum

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