since most recent mobile phones charge through a micro usb except the iphone, i'm just curious if it's really ok to charge a let's say a SE phone to a nokia charger and vice versa? both my n900 and xperia pro are fine and gets charged but i'm just curious when i noticed the volts listed on the adapter are a bit different...

nokia charger

input 100-240~/ 50-60Hz/ 160mA/ 16VA
output 5 0V=/ 1200mA

sony ericsson charger

input 100-240VAC~150mA 50-60Hz
output 5.0 VDC = 850mA