Q: How to adjust ringing duration before incoming call goes to
voicemail?
A: Standard GSM codes; i.e., works only for GSM, not AMPS, TDMA
(D-AMPS,
IS-136), CDMA, or iDEN.

Divert Voice Calls, No Answer
Delay nn seconds: max 30 seconds, in 5 second increments
Set: **61*destination*11*nn#[SEND]
Cancel: ##61*11#[SEND]
Query: *#61*11#[SEND]

May not work on all networks; does work on Cingular.
The "destination" is the voice mailbox number, not your mobile number!
Do a Query first to get the correct destination number.




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