The success of the listing has caught a lot of City folk on the hop, including the stock market bears who were selling from the word go. But they have now got a bloody nose and are frantically scrambling to unwind their positions. It is that which has been behind the sharp rise in the share price. Some brokers fear private investors may soon be tempted to join in the fun. 'They could end up sitting on hefty losses if the price goes the wrong way,' warned one broker.