Does Cisco SPA7940/7941 IP Phone works with third party open SIP server?

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    This document was generated from CDN thread

    Created by: Vivek Batra on 10-09-2010 04:35:15 AM
    Hello Cisco experts,
    We are manufacturer of SIP Call Manager. Our customers are highly demanding Cisco 7940/7941 IP-Phones to work with our SIP call manager.
    I would like to know if Cisco 7940/7941 IP Phones support firmware for standard SIP interface (RFC 3261 and others)?
    If not, what is the way to integrate 7940/7940 IP Phones with third party SIP call manager?
    -Vivek Batra