sony ericsson w715

Just picked up this phone from Vodafone. While stumbling around I came across a menu entry SIP Settings. Can't find any documentation on this, but I'm prepared to guess what it's for. Currently have no idea how it works: does it require some special program that Vod have eliminated? Does it kick in automatically when I dial a nubmer and there's a wifi network nearby?

More importantly, can't work out what to enter where. User Address's obvious enough, but where does the password go? There are separate menu items for Proxy Server and Registrar Server, each on port 5060 each with a "Realm", "Username" and "Password". But I read in another thread that voipuser doesn't have either a proxy or registrar, so I'm a bit stumped.

Any suggestions?

The cellcos do have a history of nobbling the VoIP capability on contract phones, so it wouldn't be a surprise if the VF version of firmware were different to the generic frmware on unlocked phones. I don't know this specific phone, but I have successfully used a couple of different Nokia E series phones with VoIP User.

As for SIP parameters, take a look on "My SIP Account" which shows you the details you need. There is a VU proxy, called sip.voipuser.org, and you will need to specify the VU pasword somewhere in the phone. If you can't find where to specify this in the phone hen it culd perhaps be that something is missing in the Sony firmware?