invalid large obj descriptor(0) - Mailing list pgsql-interfaces

help

I use Zeos library for C++ builder to interact with postgre server...
(it uses libpq)
when I post a blob data it fails on ApplyChanges() with
"invalid large obj descriptor(0)" error...

AutoCommit is set to false. So i dont know what is a problem.....

by the way... i've insert data with lo_import from psql's console and
everethig is ok... but when my program selects this data it fails with same
(invalid large obj descriptor) error

help
thanks

PS.
ODBC with BDE have same effect
also
servers 7.2 for win
7.3.1 for win
7.2 for linux
have same effect too