What is the story about dialing 90?

Answer 1

The story goes something like this. You're sitting at your desk in some large office. Your phone rings. The person on the other end claims to be a phone company technician and asks you to help him or her perform a test by flashing the switch hook and then dialing the special test code '90#'. Some weeks later, you get called into the boss's office to answer for some outrageously expensive international call that was billed to your extension.

The idea is that you would be transferring the call (flash) to an outside line (9) and the operator (0). You then hang up, completing the transfer of the call, and the outside caller can now ask the operator to complete a call to anywhere in the world, with your company paying premium rates for the privilege.

However, very, very few PBX managers are actually stupid enough and/or incompetent enough to allow an outside call to be transferred this way.