BUG #4980: Dblink issue

The following bug has been logged online:

Bug reference:      4980
Logged by:          Gaurav K Srivastava
Email address:      gauravgkp@gmail.com
PostgreSQL version: 8.3
Operating system:   Windows xp
Description:        Dblink issue
Details:

I have created a user by command


1:    create user posuser with password ‘pos’;
2:    create database chserver with owner = abc;
3:    GRANT ALL PRIVILEGES ON database chserver TO posuser


Now I have a schema under it named 'pos'

Now there is a table 'tickets' ie pos.tickets

Now I want to make a trigger which link another database say it is chclient
using dblink while inserting any row in tickets table.

then i got dblink function is undefined.

after running contrib/dblink.sql
i got the error while using  dblink
is
ERROR: permission denied for language c

and when I run the command

ALTER PROCEDURAL LANGUAGE C OWNER TO posuser;

then also I got the same error.

Please tell me how i make the dblink function available to posuser which is
non super user.