--- converter/other/Makefile	2011-11-19 12:05:44.000000000 +0100
+++ converter/other/Makefile.oden	2011-11-19 12:08:13.589404165 +0100
@@ -179,11 +179,11 @@
 
 ifneq ($(shell $(TEST_PKGCONFIG_LIBPNG)),)
   # pkg-config libpng works on this system
-  PNGLIB_LIBOPTS = $(shell pkg-config libpng$(PNGVER) --libs)
+  PNGLIB_LIBOPTS = $(shell pkg-config libpng$(PNGVER) --libs) -lz
 else
   ifneq ($(shell libpng$(PNGVER)-config --version),)
     # No pkg-config, but we have libpng-config on this system
-    PNGLIB_LIBOPTS = $(shell libpng$(PNGVER)-config --ldflags)
+    PNGLIB_LIBOPTS = $(shell libpng$(PNGVER)-config --ldflags) -lz
   else
     # System can't tell us where libpng is; use stuff from config.mk
     PNGLIB_LIBOPTS = $(shell $(LIBOPT) $(LIBOPTR) $(PNGLIB) $(ZLIB))