With the following code (1) you can change how long your mobile phone rings (5, 10, 15, 20, 25 or 30 seconds) .
(*)*61*+32XXXXXXXX(*)*[how many seconds]# (2) or
(*)*61*0032XXXXXXXX(*)*[how many seconds]# (2)
(1) The usage of this code is only an option in Belgium and on foreign networks supporting these codes.
(2) XXXXXXXX is a number that you want to forward your calls to. Depending on your phone you may need to use one or two * at the start of the code and before the number of seconds you're going to set.