[OpenSIPS-Users] What is protocol/port mismatch?

[opensipslist at encambio.com]

Hello list,

I'm using:

  Solaris 11 x86 (nv-b91)
  OpenSIPS 1.6.0 with TLS

...and I see this in the log:

  <warning> opensips[2717]: WARNING:core:get_send_socket: protocol/port mismatch

some hundreds of times per day (about once every 20 minutes
per registered UAC.)

I have this in the route script:

  listen = tls:name.host.tld:5061
  [...]
  t_relay("name.host.tld:5080");

There is a voicemail server (not OpenSIPS) listening on TCP (not
TLS) port 5080 on the same host. OpenSIPS and the other server
exchange traffic such as SUBSCRIBE and NOTIFY for MWI and INVITEs
to voicemail. The voicemail server sends SIP messages to OpenSIPS
port 5061 over TLS (I think.)

Question:
What exactly is the meaning of these warnings in the log, and does
it seem that I'm doing something wrong in the route script?

Thanks,
Brian