Is this a hardware of a config. problem?

[badger]

Hi, I have a 3310 on O2 and imediately after boot-up the signal goes from full to zero (no service). I tried another SIM, Vodaphone and it was exactly the same. I tried my T-Mobile and it was O.K, I made a calls etc, crystal clear. Would I be right in saying that O2 and Vodaphone are GSM900 and T-Mobile is GSM1800? Has anyone come across a phone working on 1800 but not on 900? Is this likely to be a hardware fault or is it something I can sort with Rolis or another Nokia tool?
Thanks,
Jason.

[aggelos]

well the problem maybe in coberture chip, cos its have to funcion,catch 900 and 1800 hz, and the 900 has broken.
you can resolve this changing the ic,

sorry for my english, bye!

[badger]

Compañero de las gracias. ;o) (courtesy of Babelfish so no complaints if it's wrong!!)