CONFIG_ALPHA_NAUTILUS is not available for thedefaultarchitecture x86.
Result is shown for architecture alpha

Nautilus

modulename: sys_nautilus.ko

and/or

err_ev6.ko

configname: CONFIG_ALPHA_NAUTILUS

Alpha system type
└─>Nautilus
In linux kernel since version 2.6.12  
Alpha systems based on the AMD 751 & ALI 1543C chipsets.

source code:
arch/alpha/kernel/