This will almost certainly apply to any cellphone including Blackberries.
Quite often the default period or number of rings before a call goes to voicemail is too short. You know the scenario, you’re out on a cold winters day and your phone is inside your coat. Too late you hear the muffled ring, and by the time you get the phone out from deep inside the coat it’s stopped ringing. And then you get the voicemail prompt.
Well it’s often easy to change that default period to something a bit more user friendly, but the networks don’t always make it obvious how.
In the UK iPhones are on the o2 network and this is how you change the time period before a call goes to voicemail.
Bring up the keypad and type:
**61*901*11*30# and Call.
Where 901 is the standard voicemailbox number, and 30 is the number of seconds before voicemail kicks in. Change the number of seconds to something that suits you.
You will get a response:
“Setting Registration Succeeded Voice Call Forwarding When Unanswered”.
The keypad sequence may vary on other networks, I can’t confirm that so call your network provider if the above does not work for you.