Cisco 7965g Conference Issue

I have several Cisco 7965g’s running with Asterisk. I am running firmware version SIP45.8.5-4S on them. All of these phones work great. Then I purchased a couple of additional phones that will only accept version 9.3(1)SR1 or above. After a bit of research and work I have these phones registered and working except in one area. Conferencing does not work. The soft key starts the process, allows you to dial and connect, but when you try to activate the three way the soft key does nothing. I have tried loading other softkey.xml files thinking this might help, but no luck. I have searched the web and found out that I am not alone, but I have not found any useful advice. I was wondering if anyone has had any luck resolving this conferencing issue.

hi,

have exact same problem here with cisco 7941G phones. tried load 8.5 and 9.4 with no avail.

Did you resolve the problem?

thanks