I earlier posted on how to install and activate iOS 5 beta, which Apple seeded to its developers sometime back, without needing an actual Developer Program account, which costs about $99.
Once you install and activate the iOS 5 beta on your iPhone, you might find that you are not able to make calls or even connect to your cellular network. This seems to be normal and beta versions will not allow you to connect to the cell phone network unless you add your devices’ UDID to a developer account. So, what can you do about this? Here’s what you can do to come out of this issue.
First thing to note is that you can downgrade your iPhone to the recent stable release of iOS, which is iOS 4.3.3, since Apple signs iOS 4.3.3. Downgrading seems to be a stable workaround and I have tested this out. I will keep looking if we can activate the cellular network by any means. Until then, stay tuned or follow me on twitter (@ImKarthikK).