Stefan Fiedler:

package/base/module-init-tools/module-init-tools.conf

@@ -1,3 +1,4 @@
+#!/bin/bash
 # --- ROCK-COPYRIGHT-NOTE-BEGIN ---
 # 
 # This copyright note is auto-generated by ./scripts/Create-CopyPatch.
@@ -20,7 +21,9 @@
 # 
 # --- ROCK-COPYRIGHT-NOTE-END ---
 
-confopt="$confopt --sbindir=\$root/sbin"
+sbindir="$instroot/sbin"
+var_append confopt ' ' '--sbindir=\${sbindir#$root}'
+
 export CFLAGS="$CFLAGS -I$root/usr/src/linux/include"
 
 mit_pm() {