My problem is that the ISDN adapter does not work, I have build this PC with the adapter already installed. I installed Mandriva 2005 LE.
In short, as you can see from diags i add to this post my problem manifest with this line
[Can't open /dev/isdninfo or /dev/isdn/isdninfo: No such file or directory]

[root@hek ~]# service network restart
Shutting down interface eth0: [ OK ]
Shutting down loopback interface: [ OK ]
Disabling IPv4 packet forwarding: [ OK ]
Setting network parameters: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0: [ OK ]
Bringing up interface ippp0: Activating device: ifcfg-ippp0
Loading global settings: /etc/sysconfig/isdn
Loading default settings: /etc/isdn/profile/ippp.default
Loading network settings: ifcfg-ippp0
Loading link settings: /etc/isdn/profile/link/myisp
Using profile myisp : IPPP-Default
Can't open /dev/isdninfo or /dev/isdn/isdninfo: No such file or directory in /proc/net/dev
Check ISDN hardware configuration [FAILED]

[root@hek ~]# lspci
...sniped...
00:09.0 Network controller: Cologne Chip Designs GmbH ISDN network controller [HFC-PCI] (rev 02)
...sniped...

The device like some others I tried all have the HFC-S, 2BDSO ISDN, CCDC0350E - Chipset E.G. IA1281P-STD from Planet

[root@hek ~]# uname -r
2.6.11-6mdksmp [Mandriva 2005 LE]

Hi
Same problem from me to isdn PCI-Dynalink (modprobe hisax)
isdnctrl addif ippp0
response with
Can't open /dev/isdninfo or /dev/isdn/isdninfo: No such file or directory

ls /dev/i*
/dev/initctl

/dev/input:
event0 event1 mice mouse0 mouse1

lsmod
Module Size Used by
hisax 617885 0
isdn 152897 1 hisax
slhc 7105 1 isdn

dmesg
HiSax: Linux Driver for passive ISDN cards
HiSax: Version 3.5 (module)
HiSax: Layer1 Revision 2.46.2.5
HiSax: Layer2 Revision 2.30.2.4
HiSax: TeiMgr Revision 2.20.2.3
HiSax: Layer3 Revision 2.22.2.3
HiSax: LinkLayer Revision 2.59.2.4
HiSax: Total 1 card defined
HiSax: Card 1 Protocol EDSS1 Id=asus (0)
HiSax: W6692 driver Rev. 1.18.2.4
ACPI: PCI Interrupt 0000:00:09.0[A] -> Link [LNKB] -> GSI 11 (level, low) -> IRQ 11
Found: Dynalink/AsusCom IS64PH, I/O base: 0xd400, irq: 11
HiSax: IS64PH config irq:11 I/O:d400
W6692: Winbond W6692 version (0): W6692 V00
W6692 ISTA=0x0
W6692 IMASK=0xFF
W6692 D_EXIR=0x0
W6692 D_EXIM=0xFF
W6692 D_RSTA=0xA0
Winbond 6692: IRQ 11 count 1
Winbond 6692: IRQ 11 count 5
HiSax: DSS1 Rev. 2.32.2.3
HiSax: 2 channels added
HiSax: MAX_WAITING_CALLS added

uname -a
Linux FedLinux 2.6.11-1.1369_FC4 #1 Thu Jun 2 22:55:56 EDT 2005 i686 i686 i386 GNU/Linux

P.S: Same HW-configuration on redhat9 works fine after loading hisax module

Petar