You will need to do the following:
1. Make sure the called party number that is coming in from the PSTN to the CallManager is not a valid number on the CallManager (if it is then the CallManager phone will ring)
2. Add the CME as an H.323 gateway to the CallManager using the IP address as the name.
3. Create a route pattern on the CallManager that will point to the CME (added above)
4. If you want to send the call out to the PSTN from the CME then make sure you add an outbound voip dialpeer pointing to the CallManager.
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