This alert comes from a credible source and Snopes, the Hoax Slayer, says it’s a mix of fact and fiction. Please pass on the info!
You may receive a call from an individual identifying himself as an Telstra Service technician – conducting a test on your telephone lines.
He may state that to complete the test you should touch nine(9), zero (0), hash (#) and then hang up.
Apparently by pushing 90#, you give the requesting individual full access to your telephone line, which allows them to place long distance telephone calls billed to your home phone number.
This hoax has been around for about a decade. It does not affect residential or mobile phones but it does affect businesses, government departments, hospitals that still use telephone branch services. The claim is that this scam has been originating from local jails/prisons.
Don’t press 90#!