well I use menuconfig, I've found the error online but couldn't make sense of their advice. 
this is the error:

rm -f include/asm 
( cd include ; ln -sf asm-i386 asm) 
make -C scripts kconfig.tk 
make[1]: Entering directory `/usr/src/linux-2.5.10/scripts' 
cat header.tk >> ./kconfig.tk 
./tkparse < ../arch/i386/config.in >> kconfig.tk 
drivers/isdn/Config.in: 10: incorrect argument 
make[1]: *** [kconfig.tk] Error 1 
make[1]: Leaving directory `/usr/src/linux-2.5.10/scripts' 
make: *** [xconfig] Error 2