He also hinted that AT&T could eventually place a cap on data use for the iPhone.
The company said devices like the iPhone 3G have caused dropped calls and other service issues.
AT&T said it is working to improve the network.
AT&T weighs higher fees for heavy iPhone data users
December 9, 2009 (EVANSTON, Ill.) The CEO of the company says 3-percent of iPhone users are responsible for 40-percent of the network's data traffic.
