Hi everybody, I have a brand new white iPhone 4S and I've encountered some strange problems... it started that I couldn't send SMS and then my iPhone kept losing the network and at some point it just showed "No Service" all the time anymore. By chance I found out that all those problems are solved if I just disable the PIN code. Now, without PIN, it works 100%. I don't really care about having a PIN or not, but I'm still a bit concerned if something is wrong with my phone. Does anybody have the same issue? Is it rather a hardware or software problem? And do you think it's worth to get a replacement phone? Thanks for your help!