I’ve been using the Cisco 7960 and 7940 phones for several years now, and have learned a few tips and tricks over the years. Among those is a simple *, 6 and settings key sequence that reboots a 7960 / 7940 device, which acts much like power cycling the phone. I have a friend who, to this day, thanks me for “revealing” this secret key code to him. So, FWIW, here’s the complete list of keys and URLs that you may find useful while playing around with the best-sip-phones-ever-built:

• * 6 Settings Reboots the phone as mentioned above.
• * * # Unlocks the configuration. Unless you’re using SIP versions greater than 7.X, in which case, you’d have to manually unlock the phone by going to “Settings -> Unlock Config” and entering the configuration password. Default password is “cisco”, just in case.
• Cisco document on converting a 7960/7940 from SCCP to SIP
• Archived images of Cisco SIP firmwares
• A nice, descriptive and very helpful page offered by Cat 24 that guides you through the process of upgrading the device from one of the older SCCP/SIP firmwares to the latest 8.6 version.
• An exhaustive page on cisco 79xx phones hosted by voip-info.org