Here's a great little document from Cisco directly, called "Converting a Cisco 7940/7960 CallManager Phone to a SIP Phone and the Reverse Process" Easy to do, just follow the step-by-step directions. http://www.cisco.com/en/US/products/hw/phones/ps379/products_tech_note09186a0080094584.shtml
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Here's a great little document from Cisco directly, called "Converting a Cisco 7940/7960 CallManager Phone to a SIP Phone and the Reverse Process"
Easy to do, just follow the step-by-step directions.
http://www.cisco.com/en/US/products/hw/phones/ps379/products_tech_note09186a0080094584.shtml