problem in executing a function

Hi All,

my problem is the following
i created a function the code is the following:
CREATE FUNCTION add_one (integer) RETURNS INTEGER AS '
    BEGIN
        RETURN $1 + 1;
    END;
' LANGUAGE 'plpgsql';
the code is not so complicated, i do not have any problem with this.

the problem is coming when i want to execute this function
i give a command:
select add_one(1);
and i receive an error message, that
SearchSysCache: Bad cache id 27

when i tried on teh other computer the function is working

i'm using pgsql 7.2 version on win2k operating system with cygwin 1.3.2

please help me

thanks
Ivan