"The Wi-Fi connection on Apple's recently released iPhone seems to be the source of a big headache for network administrators at Duke. The built-in 802.11b/g adapters on several iPhones periodically flood sections of the school's wireless LAN with MAC address requests, temporarily knocking out anywhere from a dozen to 30 wireless access points at a time. Campus network staff are talking with Cisco, the main WLAN provider, and have opened a help-desk ticket with Apple. But so far, the precise cau