[Asterisk-Dev] chan_sip confused when distant end sends another port for contact info

[Ed Greenberg]

I am trying to connect by sip to a distant end (Bellsouth). They have a 
sip-aware Lucent firewall. It returns a contact header with a new port. (I 
had previously posted about this and was told to turn off NAT=YES so that 
the contact header would be obeyed.

Now, I get this:

Port 5060 to Port 5060 Invite
Port 5060 to Port 5060 100 Trying
Port 5060 to Port 5060 180 Ringing
	(with Contact header directing to port 32815)
Port 5060 to Port 32815 ACK

Which looks great, but then, rather than starting an RTP stream as 
specified in the 200 OK, we get another set of invites and responses 
exactly the same way.  This goes on about four times then stops.

Any idea what's going on?

sip.conf:
[bellsouth]
type=friend
host=1xx.yy.zz.aa
context=bellsouth
disallow=all
allow=ulaw
insecure=very
canreinvite=no