LG

First of all, it is never recommended that you talk on the phone while it is plugged in at the bottom of the phone. Using it while plugged in runs the risk of damage to the connection port. With that said, YES you can use a 4400 or 6000 while it is on its "cradle" charger. It actually causes no harm or risk to the connetion port b/c it does not contact in that manner.