I still can manually connect via the installed OS program (Internet-Freigabe), but that's not very handy when you have to start a program and connect manually each time before checking your mails. And staying always online drains too much battery power.
I have the problem that my Diamond (German Vodafone ROM 22.214.171.124) cannot auto connect to the standard internet Data connection (Vodafone web). It's working fine after a clean install from scratch, but after a while without installing anything special it no longer auto connects to the internet and I got a sync error in mobile outlook. It still connects properly with Vodafone live in e.g. Google Maps, but not with the real internet.