Hi Joens,
CME 11.5 does not support 8845/65 phones. You can refer to the list of supported phones in CME version 11.5:
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucme/requirements/guide/cme115spc.html
CME 11.0 and before supported 88XX series phones in fast track mode.
Refer to the link below:
https://supportforums.cisco.com/document/12210701/fast-track-support-sip-phones
Aseem
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