How to get recordset with CallableStatemente

Dear sirs,

I am trying to get recordset from PostgreSQL database (8.1.3) with java but
I am some problem.

The operation that I would like to do is <SELECT * FROM "Congressi"> (the
table has the first letter in uppercase) (i.e. rs = st.executeQuery("select
* from \"Congressi\"");

It works with Statement object (and query string declared directly) but does
not with CallableStatement (and the query string "SELECT * FROM "Congressi"
in the function <find_congressi>) called with the statement: cs =
conn.prepareCall("{find_congressi}");

Can somebody send me a short fragment of code that call a function that
returns a set of records?

Thank you.

Domenico