Cisco 3560 does not match DSCP packets from Nortel Phone

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I have a 3560 to which I am tasked with attaching Nortel phones. Nortel recommends trusting dscp on the edge ports. I set up a policy map with ACLs to match dscp 46 for the test. I can't get a match. I then set the physical port up to trust dscp.

In both cases I can see that packets marked for dscp 46 hit the ingress side of the port, but on the egress side they exit as dscp=0.

Here is the PBR set up:

ip access-list extended signaling

permit ip any any dscp cs5

ip access-list extended voice

permit ip any any dscp ef

class-map match-any voice

match access-group name voice

class-map match-any signaling

match access-group name signaling

policy-map qos

class voice

trust dscp

class signaling

trust dscp

Why would the switch mark packets as dscp=46, then egress them as dscp=6, if the policy map is attached to the interface, or even if "mls qos trust dscp" is applied directly?

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