[Asterisk-Users] Problem with integrating ISDN PBX using NT mode

[Frederik Fix]

Hi,
I'm just in the process of replacing a crappy Siemens PBX with a new and
shiny Asterisk system. To connect Legacy equipment I hooked up a small
ISDN PBX (DeTeWe OpenCom 36) to one port on a Junghanns.net quadBRI
card. That port is configured for NT Point to Multipoint
(Mehrgeraeteanschluss) mode. Now I can place calls from the ISDN PBX to
the other Asterisk extensions but the other way around does not work.
Whenever I call from the Asterisk server to one of the extensions
connected through the ISDN PBX that extension rings for a split second
and then the call is dropped. Here is what I get on the console:

    -- Executing Macro("SCCP/13-0000002f", "standard|Zap/g2/40") in new
    stack
    -- Executing Dial("SCCP/13-0000002f", "Zap/g2/40|20") in new stack
    -- Requested transfer capability: 0x00 - SPEECH
    -- Called g2/40
  == Primary D-Channel on span 4 up for TEI 64
  == Primary D-Channel on span 4 up for TEI 66
    -- Zap/10-1 is proceeding passing it to SCCP/13-0000002f
    -- Zap/10-1 is ringing
    -- Channel 0/1, span 4 got hangup request
    -- Hungup 'Zap/10-1'
  == No one is available to answer at this time (1:0/0/0)
    -- Executing Goto("SCCP/13-0000002f", "s-NOANSWER|1") in new stack
    -- Goto (macro-standard,s-NOANSWER,1)
    -- Executing VoiceMail("SCCP/13-0000002f", "u40") in new stack
    -- Executing Goto("SCCP/13-0000002f", "default|s|1") in new stack
    -- Goto (default,s,1)
  == Channel 'SCCP/13-0000002f' jumping out of macro 'standard'
  == Primary D-Channel on span 4 down for TEI 65
  == Primary D-Channel on span 4 down for TEI 64
  == Primary D-Channel on span 4 down for TEI 66

I think I properly configured the ISDN PBX (theres not much to configure
there). Can someone help me here? What's causing the hangup request? How
could I find out?
Below is the relevant configuration.

Thanks in advance,
Frederik Fix

zapata.conf:
[channels]
switchtype = euroisdn

pridialplan = local
prilocaldialplan = local
nationalprefix = 0
internationalprefix = 00
;usecallingpres=yes

echocancel = yes
echocancelwhenbridged = yes
echotraining = 100
debug = 2

; Festnetzanschluss
signalling = bri_cpe
context=extern
group = 1
; S/T port 1
channel => 1-2
; S/T port 2
channel => 4-5
; S/T port 3
channel => 7-8

; Interner S0-Bus
signalling = bri_net_ptmp
context = intern-isdn
group = 2
; S/T port 4
channel => 10-11

extensions.conf:
[macro-standard]
exten => s,1,Dial(${ARG1},20)
exten => s,2,Goto(s-${DIALSTATUS},1)
exten => s-NOANSWER,1,Voicemail(u${MACRO_EXTEN})
exten => s-NOANSWER,2,Goto(default,s,1)
exten => s-BUSY,1,Voicemail(b${MACRO_EXTEN})
exten => s-BUSY,2,Goto(default,s,1)
exten => _s-.,1,Goto(s-NOANSWER,1)
exten => a,1,VoicemailMain(${MACRO_EXTEN})

[nebenstellen-intern]
; Konferenzzimmer
exten => 13,1,Macro(standard,SCCP/13)

; Ingrid
exten => 17,1,Macro(standard,${INGRID})
exten => 57,1,Macro(standard_ohne_ab,Zap/g2/57)

; Gavigo
exten => 60,1,Macro(standard,SCCP/60)

; Woelm
exten => 66,1,Macro(standard,SCCP/66)
exten => 68,1,Macro(standard_ohne_ab,Zap/g2/68)

; van de Beeck
exten => 40,1,Macro(standard,Zap/g2/40)
exten => 44,1,Macro(standard_ohne_ab,Zap/g2/44)

; Rohan
exten => 50,1,Macro(standard,Zap/g2/50)
exten => 59,1,Macro(standard_ohne_ab,Zap/g2/59)

; Hinterhaus
exten => 58,1,Macro(standard,Zap/g2/58)
exten => 22,1,Macro(standard,Zap/g2/22)

; fuer Testzwecke
exten => 61,1,Macro(standard,SIP/eyebeamtest)

; virtuelle Nebenstellen
exten => 30,1,Macro(virtuell)
exten => 35,1,Macro(virtuell)
exten => 48,1,Macro(virtuell)

exten => 25,1,Dial(Zap/g2/58)

[intern-isdn]
exten => 25,1,Dial(SCCP/13)
exten => s,1,DISA(no-password|intern)

[dialout]
exten => _0.,1,Dial(Zap/g1/${EXTEN:1})

[intern]
include => dialout
include => nebenstellen-intern