Thanks. Anyway I don't care if my phone shows 3G or 3.5G. I only want to have a stable connection, and it seems that in big cities (where 2G,3G 3.5G nodes co-exist) the intenet connection freezes when auto-switching from 3G to 3.5G and then back again after an inactivity period. By the time being, the only workaround is to use the 2G network, which works OK in big cities, but is very slow.