--- alevt-1.6.2//exp-gfx.c~	2007-12-03 03:56:06.000000000 +0100
+++ alevt-1.6.2//exp-gfx.c	2012-02-10 20:32:05.132342656 +0100
@@ -158,6 +158,7 @@
 #ifdef WITH_PNG
 
 #include <png.h>
+#include <zlib.h>
 static int png_open(struct export *e);
 static int png_option(struct export *e, int opt, char *arg);
 static int png_output(struct export *e, char *name, struct fmt_page *pg);