I want to install a driver for my pci modem which I have downloaded from the web. It seems it needs to rebuild the kernel. I used the package manager to install the kernel developement package. I think it should install something inside /usr/src/linux2.4.20-6 but instead of a directory this is a 0-byte file!
Also there is a symbloic link in /lib/modules/2.4.20-6 named build which refers to that directory (its target is ../../../usr/src/linux2.4.20-6 but as I mentioned above this is a dead end.
I am really frustrated because I am a newbe and I do not know exactly what to do. Please help me!!!

Maybe you can just download the kernel source from kernel.org, and rebuild from that - there's a little tutorial here:
http://www.jsward.com/linux/redhat-kernel.html

Before you start you want to check that linux properly supports your modem, as many PCI modem manufacturers refuse to provide drivers or specifications (so that we can build our own drivers) for PCI 'winmodems'.

See http://linmodems.org/ for the lowdown

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