The Financial Services Authority has secured its first criminal conviction for a "boiler room" fraud after David Mason was sentenced to two years in prison and disqualified from being a director for six years.The FSA regards boiler rooms – where investors are cold called to buy worthless, overpriced or nonexistent shares – as a "major menace to the public".After a two-year investigation, Mason pleaded guilty at Southwark crown court to 13 counts of carrying on a regulated activity without authorisation, one count of making false or misleading statements...