while sleep wifi is off
i got one 3g version and a wifi only version and been testing this out.
test1> leaving wifi version only with no activity for 5 minutes to make sure its on sleep mode. then i tried to facetime that ipad2 and it wont wake up or ring facetime on. tested several times with same result.
test2> while im calling the ipad2 wifi version (in sleep mode) i woke the device up and in less than 15 seconds facetime rings.
>i think as soon as i woke the device up, it established wifi connection why the facetime went through.
test3> tested same to the 3g version (sim card 3g data not activated) with the same result as the wifi only model.
guessing iphone4 is different as it uses mms to activate facetime.
maybe solution is to keep wifi ON while on sleep mode (battery drain?)