In his keynote address at the CTIA’s (Cellular Telephone Industries Association) big fall meeting in San Diego Thursday, AT&T’s (T) chief technology officer John Donovan denied that Apple’s (AAPL) iPhone is the reason so many of customers are complaining about his networks sluggish performance.

“I’m well aware of what’s being said in the press, in blogs, and on Twitter,” he said. “The iPhone has certainly played a role. But it’s not the only device driving growth. We have a lot of people going from basic feature phones to quick-messaging devices and other smartphones, which is driving data usage.” (link)

But his words were belied by a graphic he flashed briefly on the screen. We’ve dug up the source — a white paper published by Rysavy Research in September — and annotated it with a couple iPhone release dates.

The chart (displayed full-size below the fold) shows an 18-fold increase in data traffic during a 28-month period when voice traffic grew only two-fold.

If there were feature phones and quick-messaging devices released at the inflection points corresponding to the arrival of the original iPhone (June 29, 2007) and iPhone 3G (July 11, 2008), we must have missed them.

Below: The large chart.

[Follow Philip Elmer-DeWitt on Twitter @ philiped]