Shares in Psion Plc rocketed 41% yesterday as a feeding frenzy developed after news of Wednesday’s deal with Nokia Oy, LM Ericsson Telefon AB and Motorola Inc on handheld wireless devices (CI No 3,439). The move was heralded as a major challenge to Microsoft Corp’s ambitions for Windows CE. More than 5.5 million shares changed hands as Psion became the market’s fastest rising stock. The shares, which a week ago languished at a 1998 low of 207 pence, rose as high as 630 pence before ending the day at 602.5 pence and have doubled in the past two days alone. There was even vague takeover speculation surrounding the company, which has always been regarded as fiercely independent. The news added another lift to an IT sector which has been the market’s most buoyant sector this year – and will tempt yet another batch of companies to press forward with plans for initial public offerings.