AT&T rolled out software Friday to give iPhone users the long-awaited ability to support multimedia messaging service.

The lack of MMS capabilities has long been a hole in the iPhone platform, as competitors such as BlackBerry, Windows Mobile, and even most entry-level handsets have been able to do this for years. Apple addressed this issue with the release of the 3.0 software earlier this summer, but AT&T did not support this feature out of the gate because it wanted to ensure its network could handle the traffic.

"The unique capabilities and high usage of the iPhone's multimedia capabilities required us to work on our network MMS architecture to carry the expected record volumes of MMS traffic and ensure an excellent experience from day one," AT&T said in a statement.

The lack of MMS support has been a sore spot for many iPhone owners, and AT&T is even facing a class-action lawsuit over the missing feature in the 3.0 software. Users can get MMS support via a software upgrade through iTunes, but the firmware update will not bring picture messaging capabilities to the iPod Touch or the original iPhone.

The MMS rollout may help quiet growing criticism of AT&T from a small, but vocal, group of iPhone users regarding the carrier's network quality. AT&T has also deployed 850-MHz spectrum in major metropolitan markets to ease 3G congestion, and improved service could be vital in retaining iPhone subscribers even after AT&T loses exclusivity of Apple's touch-screen smartphone.

Another big feature of the 3.0 software is its ability to share the iPhone's cellular data connection with a laptop or other mobile computing device, but AT&T has not specified when this would be available or how much it would cost.

Part of the growth in the smartphone market will be for enterprise use, and this can quickly bring up multiple questions about security and mobility policies. InformationWeek analyzed how businesses can lock down data when it's on the move, and the report can be downloaded here (registration required).