Apple touted a variety of new features within its software update iPhone3.1, including app organiser tools within iTunes. But iPhone 3.1 has had an undesired effect on many first-generation iPhone and iPhone 3G users who receive corporate e-mail via Microsoft Exchange.

Apple support forum pages are being bombarded with reports from frustrated enterprise iPhone users who have attempted to sync information via their iPhone with Exchange servers after upgrading to iPhone 3.1, but received the following error message:

"The account requires encryption which is not supported on this iPhone."

However, corporate iPhone 3GS users appear to be unaffected. Here's why: iPhone 3.0 featured a bug that caused Exchange encryption policies for mobile devices to go unenforced, according to The Unofficial Apple Weblog (TUAW).

The original iPhone and iPhone 3G do not officially support Exchange encryption--first introduced in Exchange 2007 SP1, TUAW says--so they technically shouldn't have worked at all. In fact, Exchange encryption policies weren't enforced on any iPhone models, until iPhone 3.1 was introduced yesterday. That means even the iPhone 3GS, which officially supports Exchange encryption, was sneaking beneath those Exchange policies, according to TUAW.

This is could be both good news and bad news for Microsoft Exchange administrators; good news because the iPhone Exchange encryption requirement which should have been enforced all along is now actually in effect; bad news because frustrated iPhone and iPhone 3G users are sure to shower their administrators with questions and complaints related to the change.

Currently, there's no ideal fix. Enterprises or individual users could simply upgrade devices to the pricey new iPhone 3GS models. Or administrators could choose to disable the Exchange encryption policy. This dilemma could leave plenty of users "displeased" at the upgrade and at Apple, to say the least.

Of course, you should expect to see Apple (attempt to) offer up a fix, soon, before the early iPhone users' complaints start reverberating throughout the web and gaining strength.

Still, something tells me this isn't going to help Apple in its ongoing efforts to steal enterprise users from companies like BlackBerry maker Research In Motion (RIM).

Read more about iPhone and Exchange management here.