With the recent shift of clocks ahead 1 hour, I walked around to all my clocks with iPhone in hand adjusting them all. Went to computer and noticed iPhone was 2 minutes behind iMac time. Logged onto time.gov/com and both sites matched iMac, confirming iPhone 2 minutes slow. Did google, forum and apple support searches and found nothing that really addressed/provided fix. But in reading the various sites, some spoke about the carrier providing time when iPhone set to automatic etc. Got me thinking. I am currently home and usually use WI-FI when home. So I turned on 3G, turned off WI-FI, and lo and behold, time matched iMac, dead on. So I turned off 3G to allow Edge on, and time dropped 2 minutes behind. Turned on WI-FI, remained 2 minutes behind. Turned 3G back on and iPhone jumped to correct time. Now I wonder; Do I have a defective iPhone or is this accepted behavior? Anyone else have similar experience?