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<DIV dir=ltr align=left><SPAN class=855261819-23102008><FONT face="Lucida Sans"
color=#0000ff size=2>I'm going to try really hard not to ask why you are on 6.0
still (dang that didn't last long)...</FONT></SPAN></DIV>
<DIV><FONT face="Lucida Sans" color=#0000ff size=2></FONT> </DIV>
<DIV><SPAN class=855261819-23102008><FONT face="Lucida Sans" color=#0000ff
size=2>Check the CallManager service parameter "SIP Rel1XX Enabled". The
default value is False which means CUCM will not respond to SIP 18X messages
with PRACK.</FONT></SPAN></DIV><!-- Converted from text/plain format -->
<P><FONT size=2>-Ryan </FONT></P>
<DIV> </DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> cisco-voip-bounces@puck.nether.net
[mailto:cisco-voip-bounces@puck.nether.net] <B>On Behalf Of </B>Aman
Chugh<BR><B>Sent:</B> Thursday, October 23, 2008 1:21 PM<BR><B>To:</B>
cisco-voip<BR><B>Subject:</B> [cisco-voip] Cisco SIP phones<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV> </DIV>
<DIV>We have been working on a strange Issue with TAC , We have CUCM
6.0.1.1000.37 , The <SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Problem which we are facing is that
when we make a PSTN call from a SIP phone 3951 to a cell phone or PSTN
Phone, Ring back tone is played on 3951 IP phone even if the
mobile phone at other end is switched OFF & PSTN is
busy, A 7970 sip phone does not behave this way. I have sniffer
capture for this and I am not good at understanding SIP messages. TAC
engineer has told me to enable <FONT size=2>PRACK message , can any one tell me
what does this SIP message does and how to enable it on
CUCM.</FONT></SPAN></DIV>
<DIV><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN> </DIV>
<DIV><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">TIA</SPAN></DIV>
<DIV><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN> </DIV>
<DIV><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Aman</SPAN></DIV>
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