I just moved here from the US, and have a HTC Tmobile G1. My new job uses Vivo, and am wondering how to setup my phone to work on that network. I unlocked the phone and it worked fine on all of the India/China networks (meaning I could use different international SIM cards without any loss of function) when I was traveling there, but when I insert a Vivo SIM, it asks for the "SIM network unlock PIN (or something similar to that)." When I try to enter a PIN it keeps saying that it is unsuccessful. Does anyone know how I can get my phone to work on the Vivo network (in Sao Paulo)? If I cannot get this to work, does anyone know which carriers would support my phone? Are there any android phones available in Brazil for the Vivo network, and if not are there any Android phones available in Brazil on any network? I am willing to pay anyone for their time to assist me in setting this up. I am a Google / Android power user and really do not want to switch to a new platform! Thanks!