asterisk users - Jan 2009 - Asterisk Generating NetworkOOO (ISDN Cause Code 38)

I have a legacy ISDN PBX (Network Alchemy Argent Office) connected to
Span 2 of a Digium Wildcard TE205P.

Recently Calls from this PBX have been failing with ISDN Cause Code 38
(Network Out of Order!).  The problem seems to be getting worse and is
now effecting more calls than not (although this could just be because
I'm aware of it).

Once the ISDN PBX has decided the Network's Out of Order and torn down
the call, the Asterisk box still has the channels bridged and up.

Can anyone suggest a course of action I might take to getting this
sorted?  Do I need to change something in zapata.conf?  (included
below).

Here's the log from the ISDN PBX showing the call failing:


 2592754mS CMCallEvt:    v=1129 State, new=Ringing  old=Dialled,0,0,BState
 2592800mS CMCallEvt:    v=1129 State, new=Ringing  old=Dialled,0,0,Astate
 2595647mS ISDNL3Evt: v=0 stacknum=0  State, new=Active, old=Delivered id=1130
 2595657mS CMLineRx: v=1
            CMConnect
            Line: type=Q931Line 1 Call: lid=0 id=1130 in=0
            BChan: slot=0 chan=16

 2595657mS CMCallEvt:    v=1129 State, new=Connected  old=Ringing,0,0,BState
 2595729mS CMCallEvt:    v=1129 State, new=Connected  old=Ringing,0,0,Astate
 2596653mS ISDNL3Evt: v=0 p1=0,p2=1001,p3=5,p4=0,s1 2596654mS ISDNL3Evt: v=0
stacknum=0  State, new=NullState, old=Active id=1130
 2596659mS ISDNL3Evt: v=0 p1=0,p2=1000,p3=0,p4=0,s1 2596665mS CMLineRx: v=1
            CMReleaseComp
            Line: type=Q931Line 1 Call: lid=0 id=1130 in=0
            Cause=38, NetworkOOO

 2596666mS CMCallEvt:    v=1129 State, new=Idle  old=Connected,0,0,Astate
 2596667mS CMCallEvt:    v=1129 State, new=Idle  old=Connected,0,0,BState
 2596670mS
CALL:2009/01/0612:04,00:00:01,002,1780471800,O,0173323XXXX,0173323XXXX,Modem0,,,0

but Asterisk thinks the call is up and bridged:

asterisk*CLI> show channels 
Channel              Location             State   Application(Data)             
Zap/1-1              (None)               Up      Bridged Call(Zap/46-1)        
Zap/46-1             0173323XXXX at alchemy: Up      
Dial(Zap/g1/0173323XXXX|9999)
2 active channels
1 active calls
asterisk*CLI>

Here's the relevant bit from zaptel.conf:

#       Second port
span=2,0,1,ccs,hdb3,crc4
bchan=32-46
dchan=47
bchan=48-62
#
# Global data
loadzone=uk
defaultzone=uk


...and here's the bit from my zapata.conf for Span 2.

;
;       Network Alchemy
;
group = 2
switchtype=euroisdn
context = alchemy
usecallerid=yes
signalling = pri_net
resetinterval=100000000
callerid=asreceived
pridialplan=unknown
prilocaldialplan=unknown
useincomingcalleridonzaptransfer=yes
channel => 32-46


Can anyone help?

-- 
 Regards,
     Russell
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| Russell Brown          | MAIL: russell at lls.com PHONE: 01780 471800 |
| Lady Lodge Systems     | WWW Work: http://www.lls.com              |
| Peterborough, England  | WWW Play: http://www.ruffle.me.uk         |
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