Do your employees have a \u201cCrackberry\u201d problem? Their compulsive BlackBerry monitoring could backfire on you: Checking e-mail via BlackBerry gives employees a sense of control but leads to more stress, according to a recent study from the MIT Sloan School of Management that examined BlackBerry use and organizational behavior. And this problem starts at the top.Ninety percent of individuals at the company studied said they felt some degree of compulsion in their BlackBerry use. They check their messages not only on evenings and weekends, but also at church, at the gym, at the doctor\u2019s office and even at social gatherings. All this despite the fact that their company doesn\u2019t require them to be on call.The problem: Senior employees often establish a pattern that subordinates adopt. If everyone in an organization has a BlackBerry, continuous connection becomes the norm, says Wanda Orlikowski, who coauthored the study with fellow Sloan professor JoAnne Yates.Companies can help their employees control BlackBerry compulsion by being clear about what normal hours for checking and responding to messages are, says coauthor and doctoral student Melissa Mazmanian. \u201cThese norms and expectations should be accompanied by training that enables people to learn how to batch and queue their messages so that they can work on e-mails when convenient, without sending them out until later,\u201d she says.Some companies try to prohibit BlackBerry use during meetings. Orlikowski says some organizations require BlackBerrys to be left in a box outside the meeting room. If that seems too rigid, you might schedule breaks to allow people to check e-mails.Another tip: Use header codes (such as \u201d 1\u201d for urgent, \u201cO\u201d for no response needed) to save time.