--- src/Makefile.am.old	2011-06-17 17:31:54.078600741 +0200
+++ src/Makefile.am	2011-06-17 17:32:05.491299944 +0200
@@ -2,7 +2,7 @@
            -DDATADIR=\""$(datadir)/lucidlife"\" \
            -DDOCDIR=\""$(datadir)/doc/lucidlife"\"
 
-LIBS = $(GNOME_LIBS)
+LIBS = $(GNOME_LIBS) -lX11
 
 bin_PROGRAMS = lucidlife