diff --git a/xorg/xorg-server/post-install b/xorg/xorg-server/post-install
index 013ab141..9bf24e04 100755
--- a/xorg/xorg-server/post-install
+++ b/xorg/xorg-server/post-install
@@ -1,8 +1,8 @@
 #!/bin/sh
 
 # Give Xorg setgid to /dev/input.
-chown :input "$1/usr/bin/Xorg"
-chmod g+s    "$1/usr/bin/Xorg"
+chown :input "$KISS_ROOT/usr/bin/Xorg"
+chmod g+s    "$KISS_ROOT/usr/bin/Xorg"
 
 cat <<EOF