Thousands of Microsoft employees are concealing what might as well be a loaded weapon: an iPhone.Ten percent of its global workforce have Apple's popular smartphone tucked in their pockets, according to a recent article in the Wall Street Journal. Despite no official company rule forbidding Microsofties from using an iPhone, it is frowned upon.Very frowned upon.\n Three years ago, Microsoft CEO Steve Ballmer was none too impressed with the iPhone.During his usual fist-pumping entrance to an all-company meeting last fall, CEO Steve Ballmer grabbed an iPhone from an employee who was taking a picture of him and pretended to stomp on it. Microsoft COO Kevin Turner has reportedly discouraged Microsoft's sales force from using the iPhone, and Stephen Elop, president of Microsoft's business division and a former iPhone user, tossed his iPhone in a blender at a company meeting shortly after he was hired in 2008, according to the Wall Street Journal.You've heard of passive-aggressive. Well, this is passive-antagonistic. 'I dare you to use an iPhone,' they're all but saying. But if they feel so strongly about the iPhone, why don't they just outlaw the damn thing? Stop beating around the bush. However, such fear tactics and corporate mandates that limit personal habits are really not what Microsoft needs right now. Not in this era of openness that the company ostensibly wants to be part of.Although the top brass have been sneering at the iPhone, some of Microsoft's younger executives like entertainment and devices president Robbie Bach have reportedly encouraged using rival products to understand the competition. Top Xbox executive J Allard carries around an iPhone, according to the Wall Street Journal story. And as previously mentioned, thousands of the worker bees within the company use an iPhone (just not when they see Big Steve coming down the hall).It's highly unlikely that Microsoft's rank-and-file are using iPhones to "understand the competition." They just like them \u2014 and Microsoft has not given its own people a mobile platform to be excited about. By that measure, this could be a golden opportunity for Microsoft to prove to everyone, even its own employees, that Windows Phone 7 is a genuine mobile game changer. If Redmond is truly committed to openness and the cloud computing model, as Steve Ballmer pledged earlier this month, and if it wants Windows Phone 7 Series to compete with established mobile brands that young people love like the iPhone and BlackBerry, step one would be to lighten up about the iPhones at work situation.Ballmer and his executives should apply the philosophy of choice they've been extolling to their own workers. It would show that they trust and respect their employees, and that they are willing to learn about competing products firsthand instead of forcing a Microsoft fantasy bubble where a Windows phone is the only phone. Microsoft indeed made it more difficult to use a non-Windows phone a year ago when it tweaked its corporate cellphone policy to only reimburse service fees for employees using phones that run on Windows Phone software, according to the WSJ article.But the reality is that the Windows mobile OS is stuck in third place and the iPhone grew way higher and faster than Microsoft anticipated. Apple accounted for 25 percent of the U.S. smartphone market share numbers for the period ending January 31, according to comScore. Microsoft had 15.7 percent market share, a four-point drop from the previous period. RIM is number one, with 43 percent market share.It's understandable why Ballmer doesn't want to see any iPhones in the hallowed halls in Redmond. Would you if you were him? The iPhone's rise to glory has been a bitter pill for the top people at Microsoft to swallow. But to make a stink over workers using iPhones implies that the top ranks at Microsoft are running scared and intimidated by the iPhone's success.Ballmer should swallow that bitter pill, along with his pride, and let his people explore the iPhone. If Windows Phone 7 is as good as he says, they will have a damn good reason to come back, and so maybe will the general public.Share your thoughts. What do you think of how Microsoft, or any company, views the personal use of a competitor's product?Shane O'Neill is a senior writer at CIO.com. Follow him on Twitter at twitter.com\/smoneill. Follow everything from CIO.com on Twitter at twitter.com\/CIOonline.