CAST to integer problem

I have a function whose second parameter is defined as a varchar, but
could be an integer. I test to see if it has a character in it,
otherwise I try and do a cast to an integer. It isn't working. I'd be
grateful for some tips.

Rory

--- select output ---------------------------------------------------

[boardname := 'henners']
temporary=> select test ( 6, 'henners', 'new description');
 test
------
    1
(1 row)

[boardname := '8']
temporary=> select test ( 6, '8', 'new description');
    WARNING:  Error occurred while executing PL/pgSQL function test
    WARNING:  line 47 at assignment
    ERROR:  Cannot cast type character varying to integer

[boardname := 8]
temporary=> select test ( 6, 8, 'new description');
    ERROR:  Function test(integer, integer, "unknown") does not exist
            Unable to identify a function that satisfies the given argument types
            You may need to add explicit typecasts


--- function definition (truncated) ---------------------------------

CREATE OR REPLACE FUNCTION test
    (integer, varchar, varchar) RETURNS INTEGER
    AS '
DECLARE
    creatorid        ALIAS for $1;
    boardname        ALIAS for $2;
    description      ALIAS for $3;
    recone           RECORD;
    boardid INTEGER  ;
BEGIN
    IF boardname ~* ''[a-z]'' THEN
        -- find board identity number from select into recone
        -- <snip>
        boardid := recone.n_id;
    ELSE
        boardid := CAST(boardname AS INTEGER); -- <--- not working
        -- do some more stuf
    END IF;

    RETURN 1;

END;'
    LANGUAGE plpgsql;


--
Rory Campbell-Lange
<rory@campbell-lange.net>
<www.campbell-lange.net>