I'm sure these f*ckers do this on purpose.
they issue a mobile with an inordinately short time delay between ring and going to voice mail. that way you're forced to the call the person back and incur an outgoing call charge/use up free minutes.
Go to their website search for 'change length of ring' - 2 links, both dead.
next stop their Forums,
Even the post of the Vodafone affiliated 'staff' poster seem unwilling to provide and corroborate what the correct procedure is.
It turns out the procedure is also different between pre-pay and contract.
**61*121*11*30# for a 30 second delay.
Why is that so utterly difficult to make available to customers? Smacks of wilful intent.