I am currently in Brazil and I have used the TP2 in Mexico and Thailand with international sims. My phone is unlocked and I use a custom rom. The only thing you must do is add a new modem connection for each country and enter the GPRS data manually and then you are set to go. This site pretty much gives you all the info you need for most GSM countries and Operators.
http://www.laipac.com/gprs_setting.htm
Hope this helps.