I have an issue with my nexus one from long time ago. Sometimes when I am browsing or using some application with internet connection some people are telling me that they have problem to call me (it says that my phone is switched off). This thing is happening now when I am with 2.2 as well as it was happening before that, when I was with 2.1 version. I am not sure if this bug is there when I am using wireless but I am sure with 2G and 3G the problem exists.