ByJohn S. McClenahen The U.S. civilian unemployment rate, now 5.7%, is likely to rise as company hiring freezes are lifted and mediocre managers and workers are let go, claims Jeffrey Christian, chairman and CEO of Christian & Timbers, an executive search firm. For the past six months, says Christian, managers have had a choice between firing someone and then not replacing that employee, and holding on to someone who is mediocre but is doing something. "With hiring freezes being lifted, the mediocre workers and managers will be let go," he predicts. However, companies will be cautious about new hires -- and are employing temporary workers, including temporary CEOs, Christian says. "There is huge demand for temporary help right now all the way to the CEO level. Companies are getting a green light to clean house with the lifting of hiring freezes, but they are going to be very careful as they bring on new staffs," he stresses.