Foreign key from another database

Hi,

Can I have a reference (with cascading), to another database? Let me
try to explain the situation a little better ;-)

I have a "main" database, clients. Then I have another database. Let's
call that program1. In program1 I have a table pTable and in clients I
have a table namned Client. Like this:

\c clients
CREATE TABLE Client (
CustId Serial PRIMARY KEY,
....
);

\c program1
CREATE TABLE pTable (
pId SERIAL PRIMARY KEY,
CustId INTEGER,
....
);

I would like the data to be dropped in pTable automatically, when the
client is deleted....

/ Antti