"function has no parameter $1" - help.

I'm trying to create a trigger to enforce a constraint onto two possible
foreign tables
my function is defined as:

<-- snip -->
CREATE OR REPLACE FUNCTION
sp_check_tranitem_productid(tbl_tranitem.fld_tranitem_id%TYPE,
tbl_tranitem.fld_tranitem_type%TYPE) RETURNS
OPAQUE AS '
DECLARE
-------[Parameters]-------
pl_product_id ALIAS FOR $1;
pl_product_type ALIAS FOR $2;
<-- snip -->

but when I call the function I get the error:

function has no parameter $1

What is going wrong?

(I am using PostgreSQL 7.3.1)
,

Mike Weaver
Software Developer

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