By Neil Hughes

Published: 02:20 PM EST

AT&T confirmed Thursday that multimedia messaging capabilities will come to the iPhone a few days late, on Sept. 25 -- just after the end of summer -- bringing to an end months of waiting and speculation.

The service will be available with a software update on the launch date. The update will arrive for customers as a download from iTunes. The feature will only be available for iPhone 3G and iPhone 3GS users.

"It was important to give our customers a positive experience from day one," AT&T said. "We support more iPhone customers than any other carrier in the world so we took the time necessary to make sure our network is ready to handle what we expect will be a record volume of MMS traffic. We truly appreciate our customers’ patience and hope they'll understand our desire to get it right from the start."

AT&T officials said they have been working for months to prepare their systems and network for MMS capabilities on the iPhone, which is expected to bring a great deal of additional bandwidth the the wireless provider's network. Officials have admitted that the additional bandwidth consumed by iPhone users has been extremely taxing, resulting in dropped calls and slower service. The company plans to spend $18 billion this year to upgrade and expand its 3G network, and coverage in the Tri-State Area was recently boosted.

Tethering, however, will not be a part of the update. An AT&T spokesman told AppleInsider that the company expects to offer it in the future.

"By its nature, this function could exponentially increase traffic on the network, and we need to ensure that some of our current upgrades are in place before we can deliver the expanded functionality with the excellent performance that customers expect," he said.

It was revealed earlier that AT&T has no plans to place a bandwidth cap on iPhone users, even if they tether to share a data connection with a computer.

"We know that iPhone users will embrace MMS," AT&T said. "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. We appreciate your patience as we work toward that end."

The company said its wireless data usage rate has grown 350 percent each year for the past two years, and that is projected to continue through 2009. But the company said it wants to assure its customers that it is doing everything it can to provide the best possible service for users on its network.

"The volume of smartphone data traffic the AT&T network is handling is unmatched in the wireless industry. We want you to know that we're working relentlessly to innovate and invest in our network to anticipate this growth in usage and to stay ahead of the anticipated growth in data demand, new devices and applications for years to come."

While other overseas carriers have had MMS capability available since the launch of iPhone OS 3.0, AT&T has been late to the game, and previously only said the capability would arrive late in the summer. As the summer has crept closer to its end, users have increasingly wondered when MMS would arrive, and some even filed lawsuits over the matter.