asterisk users - Aug 2004 - zaphfc in mode TE can't dialout (dialin is OK)

Hello,
I am trying to use a HFC-PCI (CCD/Billion/Asuscom 2BD0) card in TE mode 
to dial-in and out with ISDN.
The problem is I can not get the card to dial out with a Zap channel. 
Dial-in is working. I am using bri-stuff 0.1.0-RC4 (but tried also RC3 
and RC2k). I tried all combination of "immediate",
"overlapdial",
"pridialplan". I earlier also managed to dial out with the latest
mISDN
and chan_misdn, but it was unstable and linux crashed on any dial-in. So 
I think I would rather use zaphfc.
As one can see in the BRI debug below, I tried to call ext 21 from ext 
25, the ISDN error (44) is "Requested channel not available" and 
asterisk immediately hangup.
Any help would be greatly appreciated.

Colin

P.S. lots of info following
Here the important configs and info

- Kernel 2.6.5
- zaptel.ko and zaphfc.ko loaded without options
- I am very new to asterisk :o)

### ztcfg -vv output: ###
Zaptel Configuration
=====================
SPAN 1: CCS/ AMI Build-out: 0 db (CSU)/0-133 feet (DSX-1)

Channel map:

Channel 01: Individual Clear channel (Default) (Slaves: 01)
Channel 02: Individual Clear channel (Default) (Slaves: 02)
Channel 03: D-channel (Default) (Slaves: 03)

3 channels configured.

###
colin@pbxde:/home/colin/ cat /proc/zaptel/1
Span 1: ZTHFC1 "HFC-S PCI A ISDN card 0 [TE] layer 1 ACTIVATED (F7)"
AMI/CCS

           1 ZTHFC1/0/1 ClearChannel (In use)
           2 ZTHFC1/0/2 ClearChannel (In use)
           3 ZTHFC1/0/3 HDLCFCS (In use)
colin@pbxde:/home/colin/

### Asterisk zap info: ###
pbxde*CLI> zap show channels
   Chan Extension  Context         Language   MusicOnHold
 pseudo            hfc_te          en         default
      1            hfc_te          en         default
      2            hfc_te          en         default
pbxde*CLI>

###
/etc/zaptel.conf:
loadzone=nl
defaultzone=nl
span=1,1,0,ccs,ami
bchan=1-2
dchan=3

###
/etc/asterisk/zapata.conf
[channels]
musiconhold      = default
language         = en
;
; ISDN
;
switchtype        = euroisdn
echocancel        = yes
immediate         = no
overlapdial       = no
pridialplan       = unknown
prilocaldialplan  = unknown
nationalprefix    = 0
internationalprefix = 00

context           = hfc_te
signalling        = bri_cpe_ptmp  ; HFC-S TE mode
usecallerid       = yes
usecallingpres    = yes
group             = 1
channel => 1-2

###
/etc/asterisk/extentions.conf
[...]
exten => 25,1,Wait(1)                    ; Dial in is working
exten => 25,2,Answer                    ; Answer the line
exten => 25,3,SayDigits(${CALLERIDNUM})
exten => 25,4,Hangup

exten => _0X.,1,Dial(Zap/2/${EXTEN})  ; outbound dialing is not working
[...]

##### BRI debug #####

    -- Executing Dial("SIP/2000-5418", "Zap/2/021") in new
stack
-- Making new call for cr 132
 > Protocol Discriminator: Q.931 (8)  len=27
 > Call Ref: len= 1 (reference 4/0x4) (Originator)
 > Message type: SETUP (5)
 > [> [04> [04 03> [04 03 80> [04 03 80 90> [04 03 80 90
a3> [04 03 80
90 a3]
 > Bearer Capability (len= 5) [ Ext: 1  Q.931 Std: 0  Info transfer 
capability: Speech (0)
 >                              Ext: 1  Trans mode/rate: 64kbps, 
circuit-mode (16)
 >                              Ext: 1  User information layer 1: A-Law (35)
 > [> [18> [18 01> [18 01 8b> [18 01 8b]
 > Channel ID (len= 3) [ Ext: 1  IntID: Implicit, Other Spare: 0, 
Exclusive Dchan: 0
 >                        ChanSel: Any channel selectedNo channel selected
                         ]
 > [> [6c> [6c 06> [6c 06 00> [6c 06 00 80> [6c 06 00 80
32> [6c 06 00
80 32 30> [6c 06 00 80 32 30 30> [6c 06 00 80 32 30 30 30> [6c 06 00 80
32 30 30 30]
 > Calling Number (len= 8) [ Ext: 0  TON: Unknown Number Type (0)  NPI: 
Unknown Number Plan (0)
 >                           Presentation: Presentation permitted, user 
number not screened (0) '2000' ]
 > [> [70> [70 04> [70 04 80> [70 04 80 30> [70 04 80 30
32> [70 04 80
30 32 31> [70 04 80 30 32 31]
 > Called Number (len= 6) [ Ext: 1  TON: Unknown Number Type (0)  NPI: 
Unknown Number Plan (0) '021' ]
 > [> [a1> [a1]
 > Sending Complete (len= 1)
    -- Called 2/021
< Protocol Discriminator: Q.931 (8)  len=8
< Call Ref: len= 1 (reference 132/0x84) (Terminator)
< Message type: RELEASE COMPLETE (90)
< [< [08< [08 02< [08 02 80< [08 02 80 ac< [08 02 80 ac]
< Cause (len= 4) [ Ext: 1  Coding: CCITT (ITU) standard (0) 0: 0   
Location: User (0)
<                  Ext: 1  Cause: Requested channel not available (44), 
class = Network Congestion (2) ]
-- Processing IE 8 (cs0, Cause)
    -- Channel 0/2, span 1 got hangup
NEW_HANGUP DEBUG: Calling q931_hangup, ourstate Null, peerstate Null
NEW_HANGUP DEBUG: Destroying the call, ourstate Null, peerstate Null
    -- Hungup 'Zap/2-1'
  == No one is available to answer at this time
pbxde*CLI>

##### END BRI debug #####