We've been tracking this problem for a while now ... random hiperarcs are assigning callers ips that are already in use. There isn't an overlap on the IP pools so that's not it ... my suspicion is that there is some unknown release timeout for IP's and the ARC, when disconnecting calls has to wait that amount of time to give out that IP again ... but for some reason is not waiting. Of course the users connecting get disconnected with the dupip error. Running code version V5.0.83/Non-Encr Anyone ever seen this one before? James MacDonald, CCNP Senior Platform Manager, IP Network Operations AT&T Canada Corp. 370 King St W., 6th Floor Toronto, ON M5V1J9 Ph: 416-204-5793 Fx: 416-204-5744 Emergency: 416-204-5700 (NMC Hotline) Email: james.macdonald@attcanada.com