[asterisk-bugs] [Asterisk 0014849]: SendFax function not working as expected on > 1.6.0.7

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=14849 
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Reported By:                afosorio
Assigned To:                
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Project:                    Asterisk
Issue ID:                   14849
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.0.7 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.0 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-04-07 15:51 CDT
Last Modified:              2009-05-01 06:17 CDT
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Summary:                    SendFax function not working as expected on >
1.6.0.7
Description: 
When trying to send a fax via callfile using T.38 in asterisk version
1.6.0.5 it works fine, but after upgrading to asterisk 1.6.0.7 or newer it
does not work. When receiving re-INVITE from media gateway (Cisco AS-5400)
Asterisk ends call answering 488 Not acceptable here. I am running Asterisk
under Debian kernel 2.6.18-6-686. I am attaching captures both for scenario
which works and scenario which does not work. 
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 (0104017) vrban (reporter) - 2009-05-01 06:17
 http://bugs.digium.com/view.php?id=14849#c104017 
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@all have you tried to SendFax from one asterisk to the ReceiveFAX of an
other asterisk? I have done it to encircle this issue, with curious
result:

*s = asterisk 1, SendFax
*r = asterisk 2, ReceiveFAX

1. *s send it's INVITE to *r. without T.38 in sdp, what correct, because
the receiver *r shall re-invite with T.38

2. *r now send it's re-invite with T.38 to s* (after: app_fax.c:469
transmit_audio: Fax tone detected. Requesting T38) and *s send a "100
Trying" to this T.38 re-invite.

3. Till now all is ok. But now the curious part begin:

Right after the "100 Trying" from *s the SendFax and ReceiveFAX between *s
and *r start to transmit the fax with audio T.30 (not T.38!), and before *s
send the "488 Not acceptable here", the whole fax is already and _complete_
transferred with T.30!?
   
4. After the fax is transfered, *s and *r send some "503 Unavailable" back
and forth, because the SIP transmission is also messed up then.

can someone reproduce this?

@gentian
i tested with 1.6.2-svn, but this behave should be identical with all
versions after ast_1.6.0.5 

Issue History 
Date Modified    Username       Field                    Change               
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2009-05-01 06:17 vrban          Note Added: 0104017                          
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