older TIM (Italy) SIM and 3G Data

[inquisitor]

Generally 3G networks require new 3G-compatible SIM cards (so-called USIMs), since 3G has a new authentication system which is not yes implemented in old-fashioned SIM cards. However operators can still admit 2G-authentication even on 3G networks.
In Germany T-Mobile and Vodafone have done so and so you can register on their 3G networks even with the oldest SIMs. But the other two German operators, O2 and eplus, will not accept 2G-authentication and so you need a USIM to register on their 3G network.
So it depends on the network operator's decision wether old SIMs will work on the 3G network or not.