Hello all.

I have an iPhone 3GS that has basically been a brick since March. I have T-Mobile, so I need it unlocked. The problem is that it's currently stuck on the "Insert Valid SIM" screen and I can't access the springboard. The FW is 3.1.3 and I had previously used the blackra1n unlock/jailbreak to use my phone. I want to activate it so that I may be able to use future unlock tools to make my phone usable again. My question is: if I use a friend's ATT SIM card to activate my phone, will it be safe? I don't want my friend to incur any charges for simply activating my phone. Furthermore, if it does activate with no problems, will I be able to just pop the SIM out and use my iPhone as an iPod Touch in the interim until I can safely jailbreak/unlock it? Thanks for your time.