diff -pur xbubble-0.5.8.orig//src/loadpng.c xbubble-0.5.8/src/loadpng.c
--- xbubble-0.5.8.orig//src/loadpng.c	2003-09-30 08:55:20.000000000 -0400
+++ xbubble-0.5.8/src/loadpng.c	2010-03-09 15:35:19.100219706 -0500
@@ -55,7 +55,7 @@ unsigned char * load_png_file( const cha
   }
   /* ensure that we opened a PNG file */
   fread( header, 1, 8, fd );
-  if ( ! png_check_sig( header, 8 ) ) {
+  if ( png_sig_cmp( header, 0, 8 ) ) {
     fclose(fd);
     fprintf(stderr,_("File %s does not have a valid PNG signature.\n"), file);
     return NULL;