[asterisk-bugs] [Asterisk 0012437]: Asterisk negotiates only T.38 when answering even if the other end offers audio

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12437 
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Reported By:                marsosa
Assigned To:                file
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Project:                    Asterisk
Issue ID:                   12437
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     ready for testing
Asterisk Version:           1.4.18 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2008-04-14 08:31 CDT
Last Modified:              2009-03-25 10:09 CDT
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Summary:                    Asterisk negotiates only T.38 when answering even if
the other end offers audio
Description: 
One of our gateways (audiocodes mp-118) offers ulaw,g729 and t.38 when an
incoming call is sent to asterisk, and asterisk answer() with t.38 only,
instead of using ulaw. T.38 is enabled on the gateway because this is
needed for reinvites, if i disable it, the call works ok but fails later
when the ata wants to do reinvite for receiving faxes with t.38 '488 not
acceptable'.
The main problem here is that, after answering with t.38, asterisk sends
invites with t.38 only to the ip phones, and they rejected with not
acceptable.
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 (0102166) afu (reporter) - 2009-03-25 10:09
 http://bugs.digium.com/view.php?id=12437#c102166 
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Hi file!
The reinvite of T38 seem to work, but there is another issue. Teles sends
codec + T38 for every call, even if its voice. 

verbose says: add audio = 1 add t38 = 0
but Autodestruct on dialog '2cf6ffdd63b70b40308d84f75506b793 at ip-asterisk'
with owner in place (Method: INVITE)

so a voice call would last only 32 secs.

see attached file t38-error.txt with verbose 3, and sip traces for
outgoing and incoming side

thanks!

greetings from austria, andy 

Issue History 
Date Modified    Username       Field                    Change               
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2009-03-25 10:09 afu            Note Added: 0102166                          
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