2DegreesCare:

Ivelisse: The phone is 3G also, my carrier on Mexico offers 3G and i would use it back there. Checking on the website of my carrier back home there says the phone gets on their network 3G 850 and 1900, GSM 850, 900, 1800, 1900.

Looking at the mexican carrier website they offer international roaming here on NZ on the Vodafone network for my cellphone and is listed as 3G on the 2100mhz frecuency, and on GSM 900 and 1800, so, what do you think? Vodafone is my best option with this phone here on NZ?

Edit: If i use this code *#*#4636#*#* on the option of "set the prefered network" i have selected "WCDMA preferred" would be better if i change it to "GSM only", "WCDMA only", "GSM auto (PRL)", "CDMA auto (PRL)", "CDMA only", "EvDo only", "GSM/CDMA auto (PRL)", or "Unknown"

Set it to GSM (2G) only and you should get a signal.  Our network is 900MHz GSM and HSDPA at 2100MHZ within our Mobile Broadband Zones.  Data is provided using both GPRS and EDGE technology and outside our canopy you will need to have 'Data Roaming' enabled. 

Hope that helps. 
^POB