A friend of mine got an unlocked iphone the other day and all seemed to be working with the exception of his Voicemail button. This wasn’t an issue I’d had with mine but a quick Google turned up the necessary information. Many thanks to the guys on the iPhone Dev Team WiKi – not linked at their request.

There is a code you can dial to set this, as with the SMS Centre number discussed last time: *5005*86*xxx# – xxx is the number you dial to access your Voicemail. For example; on UK Vodafone you dial 121 to reach your Voicemail so the code would be *5005*86*121#.

Hope that helps….