Two important things to remember:
1) You have to have make sure the MGCP enabled dial-peers appear before any H323 dial-peers. These are usually the dial-peers that start with 999 or something similar.
dial-peer voice 999020 pots
service mgcpapp
port 0/2/0
2) Then you have to add the following voiceport configuration for PLAR
voice-port 0/2/0
connection plar
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