What exactly goes wrong? Tell us where you get stuck. The more information the better.
I don't have Vodafone mail so I don't know any more than I've read. I cant guarantee this is accurate.
It appears that you need to enter the basic settings, let it try to setup the account automatically, then enter the more advanced information. After that it should all work.
Here's some info I've grabbed of the Vodafone site, it's not easy to find thats for sure.
Incoming server – pop.vodafone.co.nz
Outgoing server – smtp.vodafone.co.nz
Username – username@vodafone.co.nz
SSL – Off
It appears that you can use smtp2.vodafone.co.nz, with no username or password, but it won't work over WIFI. There is also the suggestion that you may need to use port 25 (not sure on that one).
Hopefully one of our friendly members here can be more specific than me.
Worst case, you could always phone Vodafone…