Since its release two weeks ago, Apple has taken an enormous amount of criticism over iOS 6. The bulk of the heat has come over the new, so-called inferior Maps application, but there have also been complaints of Wi-Fi and App Store issues.

In fact, according to a new report today, some major companies are urging their employees not to update their iOS devices to the new firmware. But it’s not because of Maps or Wi-Fi problems. It has to do with a major Exchange bug…

MacRumors reports:

“MacRumors has learned that at least one Fortune 500 company is requesting that its employees not upgrade to iOS 6 over a bug with Microsoft Exchange meeting invitations.

The issue appears when users decline a meeting invitation from an iOS 6 device. Instead of simply sending a notification to the meeting organizer that the user will not attend, iOS 6 is sending meeting cancellation notices to the entire distribution list, effectively canceling the invitation for all attendees.”

Employees who are already on iOS 6 are being asked not to accept or decline calendar appointments until the problem has been resolved. Both Apple and Microsoft are aware of the issue, but there’s been no word from either company on a fix.

The calendar bug has spawned a short thread in Apple’s online support forums, as has another Exchange issue involving push email. Here’s hoping Apple can come up with an answer quick, so it doesn’t risk angering its enterprise users.

Have you seen any issues with Exchange accounts in iOS 6?