ISDN modem problems (IRQ?)

Hi,
I seem to be having problems getting hisax to find my Teles.BRI/PCI ISDN modem. (have tried passing type=21 to hisax module, but it won’t find the card).
According to lspci or scanpci it’s there all right, on IRQ 10. The problem is not the card itself, since it works fine with win95/98/2k.
Could the problem be that my USB controllers also have IRQ 10? If so, is there a way of forcing either USB controllers or ISDN modem onto another IRQ?

I am using Mandrake 8.0, with hisax and isdn4linux that came bundled with it (should be recent enough, no?)

Thanks in advance!