Insert Rule

I'm trying to prevent any further input of a particular field value via an
insert rule with the following rule.

CREATE OR REPLACE RULE rule_foovalue AS

ON INSERT TO foo

WHERE new.foovalue = 1 DO SELECT fooexception.fooexception

FROM fooexception() fooexception(fooexception);

Basically the stored procedure that it calls raises an exception. The
behavior I wanted\excepted was to call the stored procedure when foovalue =
1 and to execute a regular insert when foovalue <> 1. What its doing is
calling the stored procedure when foovalue = 1, that part works just fine.
However, when I try to insert a record into foo with any other value besides
1 it actually inserts the record but doesn't return the # of rows affected.
Is there something else I need to add to the rule so that it returns the
number of rows affected like normal?

Thanks,
Curtis