$ fakeroot debian/rules updateconfigs
dh_testdir
Processing i386 (i386) ... 
Running silentoldconfig for config.386 ... 
make[1]: Entering directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
  HOSTCC  scripts/basic/fixdep
  HOSTCC  scripts/basic/docproc
  GEN     /home/adam/kernel-fu/linux-source-2.6.20-2.6.20/build/Makefile
  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/kxgettext.o
  SHIPPED scripts/kconfig/zconf.tab.c
  SHIPPED scripts/kconfig/lex.zconf.c
  SHIPPED scripts/kconfig/zconf.hash.c
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/conf
scripts/kconfig/conf -s arch/i386/Kconfig
make[1]: Leaving directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
Running silentoldconfig for config.generic ... 
make[1]: Entering directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
  GEN     /home/adam/kernel-fu/linux-source-2.6.20-2.6.20/build/Makefile
scripts/kconfig/conf -s arch/i386/Kconfig
make[1]: Leaving directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
Running silentoldconfig for config.server ... 
make[1]: Entering directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
  GEN     /home/adam/kernel-fu/linux-source-2.6.20-2.6.20/build/Makefile
scripts/kconfig/conf -s arch/i386/Kconfig
make[1]: Leaving directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
Running silentoldconfig for config.server-bigiron ... 
make[1]: Entering directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
  GEN     /home/adam/kernel-fu/linux-source-2.6.20-2.6.20/build/Makefile
scripts/kconfig/conf -s arch/i386/Kconfig
make[1]: Leaving directory `/home/adam/kernel-fu/linux-source-2.6.20-2.6.20'
Running splitconfig.pl ... 

debian/bin/oldconfig: line 73: /home/adam/kernel-fu/linux-source-2.6.20-2.6.20/debian/bin/splitconfig.pl: Permission denied
make: *** [updateconfigs] Error 1