Struggling smartphone maker BlackBerry has fired its CEO Thorsten Heins, who leaves with a $22 million severance package. He will be replaced at the end of November by John Chen former CEO of Sybase. The move comes as the company turns its back on a $4.7 billion rescue deal from its principal shareholder Fairfax Financial, in favour of a plan to raise $ 1 billion in convertible bonds: Fairfax has pledged to buy $250 million worth of them.