Can't insert ISDN module

[olafsmail@web.de]

Hi there

I'm sorry to bother you, but nobody can give me an answer to my
problem. I'm using the current potato release of Debian 2.2
(vanilla Kernel 2.2.17) on a 486 Dx 33, 8megs ram, 120megs hd 
machine. This shall be our ISDN router for me and my friends using 
isdnutils_3.0-20. I have got a Teles 16.3 card which was runnig 
fine under RedHat 6.0 (in my desktop, but Redhat is too f*cking big 
for the 486) Anyway I'm switching to Debian now :-)


The problem occurs already when inserting the isdn.o module:

matrix:/home/og# modprobe isdn
/lib/modules/2.2.17/misc/isdn.o: init_module: Device or resource
busy
Hint: this error can be caused by incorrect module parameters,
including invalid IO or IRQ parameters
/lib/modules/2.2.17/misc/isdn.o: insmod
/lib/modules/2.2.17/misc/isdn.o failed
/lib/modules/2.2.17/misc/isdn.o: insmod isdn failed


This is what had been logged to /var/log/kern.log:

Oct  9 16:03:43 matrix kernel: CSLIP: code copyright 1989 Regents
of the University of California
Oct  9 16:03:43 matrix kernel: Could not allocate modem xmit-buffer
Oct  9 16:03:43 matrix kernel: isdn: Could not register tty devices

Thanks in advance

-olaf