[VoiceOps] ACME Contact Header rewrite

Anyone know how to disable the Contact rewrite? I'm trying to build a PBX in a Metaswitch and the configured SIP binding has an ACME as it's proxy. I have outbound working fine, but it breaks on inbound as the MS is looking for the PBX IP in the Contact header, not the ACME's. I understand the point is for the signaling to come back to the ACME, but the proxy setting in the SIP binding takes care of that. Lee