--- config/_arch-n-opsys.orig	2014-08-22 15:20:03.000000000 +0200
+++ config/_arch-n-opsys	2014-08-23 14:19:47.056122710 +0200
@@ -85,6 +85,8 @@
     HEAP_OPSYS=bsd
     case `uname -m` in
       *86) ARCH=x86;;
+    # Fall back to x86 compatibility mode.
+      amd64) ARCH=x86;;
       *) exit 1;;
     esac
     ;;