Why not (OID) in JDeveloper10g?

Hello!,
Using JDeveloper10g (ORACLE) I can connect to PostgreSQL database
on local machine;
BUT! when trying to open informations on table structure, I receive this ER=
ROR=20
MESSAGE=20
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See image attached!






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and I'can't access table structure informations (I.E. ftable.fields list)!


This is what says Oracle about this same error on his help on line into=20
JDeveloper10g.
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Cause: A database failure occurred while trying to generate an object ID (O=
ID)=20
and object reference (REF). When a new row is created on an entity which ma=
ps=20
to an Oracle object table, an OID and REF for the new row are generated. Th=
is=20
executes a SQL statement like select a.oid, make_ref(, a.oid) ... Somehow,=
=20
this statement is failing. Action: Check the following: Are you using the=
=20
right version of Oracle database? Is the table in question an object table?=
=20
This error normally carries a detail exception from the database, which wil=
l=20
give further information about the database failure. Take a look at the=20
detail exception and address the database problem.=20
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Do anyone knows why this happen?, is it possible to correct already the=20
problem?, or anyone does encountered the same problem?=20
--=20
Roberto Della Grotta