Description:
Adds a new mail blacklist entry if access is REJECT.
Input Variables:
$session_id, $client_id, $params
Parameters (in $params):
server_id (int(11))
source (varchar(255))
access (varchar(255))
type (set('recipient','sender','client'))
active (enum('n','y'))
Output:
Returns the ID of the newly added mail blacklist entry.