I have a 2821 running CME 4.1 with CUE 3.0.1. I have a few SIP endpoints (Sipura & Linksys SPAs and a Mitel 5055) running off of it. Everything works perfect, except when any one of these endpoints tries to call voicemail (or any service DN connected to the Unity Express, for example the auto attendant). The SIP endpoint receives audio correctly, but is not transmitting any DTMF or voice to the CUE. Any ideas what might be the problem?
I have tested these scenarios (voice & DTMF):
SIP phone <-> SCCP phone (OK)
SIP phone <-> SCCP FXS port on local router (OK)
SIP phone -> PSTN via SIP trunk (OK)
SIP phone -> PSTN via FXO port (OK)
SIP phone -> CUE pilot number (no outbound audio, no DTMF)
SIP phone -> CUE auto attendant (no outbound audio, no DTMF)
<-> meaning that I have called to and from either endpoints.