diff -r 8c959ab35832 -r 1e2f42892ffe common/autoconf/spec.gmk.in
--- a/common/autoconf/spec.gmk.in	Tue Feb 11 10:44:23 2014 +0100
+++ b/common/autoconf/spec.gmk.in	Thu Feb 20 10:07:46 2014 -0500
@@ -645,6 +645,15 @@
 # Read-only single-machine data
 INSTALL_SYSCONFDIR=@sysconfdir@
 
+####################################################
+#
+# Libraries
+#
+
+USE_EXTERNAL_LIBPNG:=@USE_EXTERNAL_LIBPNG@
+PNG_LIBS:=@PNG_LIBS@
+PNG_CFLAGS:=@PNG_CFLAGS@
+
 
 ####################################################
 #