The 1416 phone we supplied at one of our client is giving some issues.They presently have 5410 digital phones and an Ip office 406 v2 running on release 6.1(12) firmware.The digital stations are connected to the ip office through the digital expansion modules.The issue is that once we unplug the 5410 phone and connect the new 1416 digital handset to the same network port.The new 1416 phone will display "firmware upgrade required" after some minutes the phone will display "waiting for upgrade" and the phone will hang on that state till it is restarted.We noticed that if we try to connect the 5410 phone back to that same port we used for the 1416 phone the 5410 wont work until we perform an hard reboot on the entire ip office and the digital expansion module.This sounds strange and the guys in that office does not want us to connect the 1416 to the expansion module or card because it will make the port unusable until the entire system is restarted.Please i need your advise on this