Is this a compatibility problem to integrate Presence 6.0 with CallManager 5.12?

We are integrating CUPS6.0 with CCM5.12 in a project. After one week efforts, everything is working fine except for the phone presence status on CUPC. The status of contacts logged-in always shows “available” or “idle”, but never shows “one the phone”. In the CUPC preferences configuration, I configured -Show me as “on the phone” - Whenever I am on the phone, so it should show “on the phone” status if the associated phone is used. The problem looks like the CallManager doesn't send “Publish” message to Presence.

We also have done the integration of CUPS6.0 and CCM6.0 in our Lab, and there is no this problem.

I am not clear about the configuration from Cisco Docs. Here is the quote from Cisco Unified Presence Settings:

################################

Enable Publish to Cisco Unified Communications Manager check box

Note : This field only displays when you connect to Cisco Unified Communications Manager Release 6.0 or higher.

Cisco Unified Communications Manager SIP Publish Trunk

Note : This field only displays when you connect to Cisco Unified Communications Manager Release 6.0 or higher.

#####################################

With the integration of CCM 5.12, I can't see the “Enable Publish to Cisco Unified Communications Manager” check box and “Cisco Unified Communications Manager SIP Publish Trunk” in the Presence Settings. Does this mean that it should work without these configurations or it is a compatibility problem here? If it should work, what can I do about it?