Olá, recentemente precisei adicionar uma placa de redes dessas num servidor HP com Debian nem tenho a necessidade de tanta velocidade, só pq foi só essa placa q funfa!
iniciei os problemas.
primeiro nao tinha os headers, e eu instalava, mas nao funcionavam, consegui um passo a passo daqui, e pude levar o erro mais adiante
agora que já instalei os headers, dá o seguinte erro:

Create tmp dir (/tmp/Sk98IaQdApqKOhRIGEkqFeXmD) [ OK ]
Check user id (0) [ OK ]
Check kernel version (2.6.18-5-686) [ OK ]
Check kernel symbol file (/proc/kallsyms) [ OK ]
Check kernel type (SMP) [ OK ]
Check number of CPUs (2) [ OK ]
Check architecture (found) [ OK ]
Set architecture (i386) [ OK ]
Check compiler (/usr/bin/gcc) [ OK ]
Check mcmodel flags (none) [ OK ]
Check module support (/sbin/insmod) [ OK ]
Check make
(/usr/bin/make) [ OK ]
Check archive file (sk98lin) [ OK ]
Check kernel gcc version (4.1.2) (Kernel:4.1.2 == gcc:4.1.2) [ OK ]
Check sk98lin driver availability (not loaded) [ OK ]
Check kernel header files (/usr/src/linux) [ OK ]
Unpack the sources (done) [ OK ]
Check sources for .config file (/usr/src/linux/.config) [ OK ]
Copy and check .config file (done) [ OK ]
Check the mem address space (highmem) [ OK ]
Change IOMMU (disabled) [ OK ]
Create new .config file (done) [ OK ]
Execute: make oldconfig (done) [ OK ]
Check kernel header version (not recognized) [ warn ]
Check kernel functions (Changed: nothing) [ OK ]
Compile the kernel (error) [ failed ]

An error has occurred during the compile proces which prevented
the installation from completing.
Take a look at the log file install.log for more informations.
Installation of sk98lin driver module failed.

e o final do install.log é:

misc/Kconfig
misc/Configure.help

+++ Compile the driver
+++ ====================================
make: Entrando no diretório `/usr/src/linux-source-2.6.18'
Building modules, stage 2.
MODPOST
make: Saindo do diretório `/usr/src/linux-source-2.6.18'
+++ Compiler error

não sei o que pode ser agora, e nem como posso resolver!