diff -ur -EbwB libwmf-0.2.8.4/configure.ac libwmf-0.2.8.4/configure.ac
--- libwmf-0.2.8.4/configure.ac	2005-07-27 22:48:39.000000000 +0200
+++ libwmf-0.2.8.4/configure.ac	2010-02-09 17:09:57.000000000 +0100
@@ -519,6 +519,20 @@
 dnl "png.h" includes "zlib.h"
 CPPFLAGS="$CPPFLAGS $WMF_Z_CFLAGS"
 
+for l in libpng libpng14 libpng12; do
+  AC_MSG_CHECKING(for $l)
+  if `$PKG_CONFIG --exists $l` ; then
+    AC_MSG_RESULT(yes)
+    PNG='png'
+    WMF_PNG_CFLAGS=`$PKG_CONFIG --cflags $l`
+    WMF_PNG_LDFLAGS=`$PKG_CONFIG --libs $l`
+    break
+  else
+    AC_MSG_RESULT(no)
+  fi
+done
+if test x$PNG != xpng; then
+  AC_MSG_RESULT(no)
 AC_CHECK_HEADER(png.h,[
 	AC_CHECK_LIB(png,png_write_image,[
 		if [ test "x$PNG_DIR" != "x" ]; then
@@ -531,6 +545,7 @@
 	],-lz -lm)
 ],[	AC_MSG_ERROR(* * * unable to find "png.h" which is required by libwmf * * *)
 ])
+fi
 
 AC_DEFINE(HAVE_LIBPNG,1,[define if you have libpng])
 GD_DEFS="$GD_DEFS -DHAVE_LIBPNG"
diff -ur -EbwB libwmf-0.2.8.4/src/extra/gd/gd_png.c libwmf-0.2.8.4/src/extra/gd/gd_png.c
--- libwmf-0.2.8.4/src/extra/gd/gd_png.c	2005-07-27 22:35:06.000000000 +0200
+++ libwmf-0.2.8.4/src/extra/gd/gd_png.c	2010-02-09 17:21:40.000000000 +0100
@@ -136,7 +136,7 @@
   /* first do a quick check that the file really is a PNG image; could
    * have used slightly more general png_sig_cmp() function instead */
   gdGetBuf (sig, 8, infile);
-  if (!png_check_sig (sig, 8))
+  if (png_sig_cmp (sig, 0, 8))
     return NULL;		/* bad signature */
 
 #ifndef PNG_SETJMP_NOT_SUPPORTED