How can we add Cisco Wireless IP phone 7921 in Cisco Call Manager 4.1(3)?

We are not able to Configure Cisco Wireless IP Phone 7921 in Call Manager Server 4.1(3)because Call Manager does not support 7921 Models, so do we need to install Cisco 7921 firmware in Call Manger Server or do we need to upgrade the call manager?We don't have any service contract to upgrade the call manager the only option is Firmware if it can support Cisco Wireless IP Phone 7921. We have call manager version 4.1(3)sr1. Does it Support Cisco Wlreless IP Phone 7921 ?We have a Cisco Call Manger (Publisher and Subscriber) Cluster with more than 500 Phones registered and running.Will there be some down or any impact on the registered Phones?

Please Click here to download the latest device pack for 4.1(3) (Cisco login required)
NOTE: Apply this patch to all of your Cisco Call Manager servers, beginning with the publisher server and TFTP server.

1. When applying this Device Package to enable new device support, a cluster-wide reboot is required for those devices to register successfully.
2. A cluster wide reboot is not required when running to update existing firmware/support.
3. If installing on a Cisco Unified Call Manager version earlier than 4.1(3)sr2, the following message will be displayed: “Install on all nodes is required. All nodes will be rebooted as part of the installation.”
4. If installing on Cisco Unified Call Manager 4.1(3)sr2 (recommended), the following message will be displayed: "Install on Publisher and TFTP server is required. Installation on all nodes is highly recommended."
5. A cluster wide install/reboot is required.

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