--- config.mk.orig	2013-01-12 17:59:23.000000000 +0100
+++ config.mk	2013-01-12 17:59:48.000000000 +0100
@@ -1,6 +1,6 @@
 # paths
-X11INC = /usr/X11R6/include
-X11LIB = /usr/X11R6/lib
+X11INC = $(PREFIX)/include
+X11LIB = $(PREFIX)/lib
 
 # Xinerama
 XINERAMALIBS = -L${X11LIB} -lXinerama