diff --git a/scripts/symbols.dfn b/scripts/symbols.dfn
index 429fe2384..d3c722cf1 100644
--- a/scripts/symbols.dfn
+++ b/scripts/symbols.dfn
@@ -1,7 +1,7 @@
 
 /* symbols.dfn - find all exported symbols
  *
- * Last changed in libpng 1.5.0 [April 18, 2010]
+ * Last changed in libpng 1.5.0 [April 24, 2010]
  * Copyright (c) 1998-2010 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
@@ -41,7 +41,6 @@
 #define PNG_ERROR_NUMBERS_SUPPORTED
 #define PNG_READ_BIG_ENDIAN_SUPPORTED  /* should do nothing! */
 #define PNG_INCH_CONVERSIONS_SUPPORTED
-#define PNG_READ_QUANTIZE_SUPPORTED
 #define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
 
 #undef PNG_H