We've been experimenting with deploying spectralink 8440 phones to replace our failure prone 6140 Avaya phones. I have SIP3 licenses installed and have been able to get the 8440s to connect and register no problem. They can make and recieve phone calls and seem to work great. The one downside is that I cannot get them to transfer calls to another SIP device (SIPdroid for android or another connected 8440). When I try and transfer it will call the new device but says transfer failed when I try to complete the transfer. The vendor is stumped, has anyone else ran into this? I am using them on rls 7.5 CS1000 switch. Let me know, thanks!