Can't find relation oid

Hi,

I have the following problem:

I use libpq inside SRF functions (like in dblink) and I create some tables
to store results coming from remotly executed queries. (These tables are not
temporary cause I want to use them later as a form of cache.) Then I try to
open these tables to get the results. Actually I modify an already available
Query to refer to these new tables instead of the correspoding local tables.
To do so I need the Oids of theses new tables which I get using the
following query:

select oid from pg_class where relname='foo'

The problem is that when the new tables are created for the first time, the
above query returns no results and the whole thing fails.Everything works
fine if they have already been created by a previous attempt to run my SRF.

I tried to isolate each step (creating tables, retrieving results) in a new
transaction block (like in testlibpq.c example in the documentation) but
with no result. Maybe the whole process described above runs in a sigle
transaction block i.e. that of my SRF(?). I'm a little confused here.

Any ideas?

Regards,
Ntinos Katsaros