I have a Nextel i530, which is supposedly GPS enabled, with NMEA output capability. The manual and associated software menus report to have user selectable "privacy controls" on the GPS software, but state that these are bypassed on 911 calls, and that the phone's location can always be made available to it's owner/administrator.

A fix recently came out from Motorola for the "A-GPS" (assisted global positioning system) featured in these handsets. I understand this to mean the iDEN network sort of "helps along" the GPS receiver when possible to acquire an initial position. Must've been a pretty serious bug as Motorola is now giving away the USB data cable along with a CD-ROM containing the software patch. They had been charging $30 up until recently for the cable alone.

FWIW, I've never, ever gotten the i530 to acquire a GPS signal, either before or after the software update...tried about a dozen times total. In the last few months the phone has been telling me the "satellite data is outdated, call 800-xxx-yyyy to buy". Guessing this is the almanac data, which, in theory would only mean it should take longer to get a fix. No joy there.

Let's just say i'm not counting on E911 being able to lock on to my position in an emergency, and I would definitely not substitute it for a real GPS unit.