Hello, I am trying to activate the check blacklist function but I keep getting an error. The script I run is this;

if(!check_blacklist("global_blacklist")){
         sl_send_reply("403","Forbidden");
           exit;
            }

When I restart kamailio I get the following error; 

failed to find command check_blacklist

Is there any module I will need to activate to make this work? 


Regards,
Arun