init_module: device or resource busy

Hi, I am trying to setup a 486 box (8mb ram, 200mb hd) with suse 6.4 as a gateway with an isdn dial-up connection. I am using a fritz card classic /avm a1. At first, I used Yast1 for setup, but when this did not work, i tried myself... Now, when i try to insmod isdn.o i get init_module: device or resource busy In /var/log/messages it says: gate kernel: couldn't allocate modem xmit buffer gate kernel: couldn't register tty devices The card is working, the isdn line is up and the configured interrupts and io ports are unused. Also, no loaded module uses the card. I heard the problem could be lack of memory??? Any guesses? Help _very much_ appreciated!!! chris ----- uzsdhm@uni-bonn.de