diff --git a/scripts/makefile.darwin b/scripts/makefile.darwin
index 924eca2..330d7cc 100644
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -23,7 +23,7 @@
 RANLIB=ranlib
 
 PNGMAJ = 0
-PNGMIN = 1.2.6
+PNGMIN = 1.2.7beta1
 PNGVER = $(PNGMAJ).$(PNGMIN)
 LIBNAME = libpng12
 
@@ -167,7 +167,17 @@
 install: install-static install-shared install-man install-config
 
 # If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
 
 test-installed:
 	$(CC) $(CFLAGS) \