Default [Q] Visual Voicemail

Hi all
My question is does the visual voicemail option/ settings only show on the phone if your carrier supports it?
I am currently on Vodafone UK who do not support VVM and I'm going to move to O2 but currently the handset does not show any of the VVM options! Will this change if I move to O2 assuming I have VVM on my contract?

Can anyone confirm if the leaked Schubert mango rom has vvm functionallity?