Comment Thst's 14 year old news (Score 4, Informative) 122
Many governments have warned industrialists not to discuss secrets when using a mobile phone near the country borders. Only the radio channels are encrypted in GSM, lawful interception happens on the wired network that interconnects the base stations so eavesdropping on A5/1 is mostly used when lawful interception is not an option, e.g. listening to the GSM traffic of other countries.