diff --git a/libpng-manual.txt b/libpng-manual.txt
index 16ed29ea5..38fed783c 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.5.6rc02 - October 26, 2011
+ libpng version 1.5.6rc02 - October 27, 2011
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.5.6rc02 - October 26, 2011
+ libpng versions 0.97, January 1998, through 1.5.6rc02 - October 27, 2011
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
 
@@ -4555,6 +4555,9 @@ left parenthesis that follows it:
 We prefer #ifdef and #ifndef to #if defined() and if !defined()
 when there is only one macro being tested.
 
+We prefer to express integers that are used as bit masks in hex format,
+with an even number of lower-case hex digits (e.g., 0x00, 0xff, 0x0100).
+
 We do not use the TAB character for indentation in the C sources.
 
 Lines do not exceed 80 characters.
@@ -4563,7 +4566,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 XIV. Y2K Compliance in libpng
 
-October 26, 2011
+October 27, 2011
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
diff --git a/libpng.3 b/libpng.3
index 668462355..b8f5c39d8 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "October 26, 2011"
+.TH LIBPNG 3 "October 27, 2011"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.5.6rc02
 .SH SYNOPSIS
@@ -977,7 +977,7 @@ Following is a copy of the libpng-manual.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.5.6rc02 - October 26, 2011
+ libpng version 1.5.6rc02 - October 27, 2011
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
@@ -988,7 +988,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.5.6rc02 - October 26, 2011
+ libpng versions 0.97, January 1998, through 1.5.6rc02 - October 27, 2011
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
 
@@ -5533,6 +5533,9 @@ left parenthesis that follows it:
 We prefer #ifdef and #ifndef to #if defined() and if !defined()
 when there is only one macro being tested.
 
+We prefer to express integers that are used as bit masks in hex format,
+with an even number of lower-case hex digits (e.g., 0x00, 0xff, 0x0100).
+
 We do not use the TAB character for indentation in the C sources.
 
 Lines do not exceed 80 characters.
@@ -5541,7 +5544,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 .SH XIV. Y2K Compliance in libpng
 
-October 26, 2011
+October 27, 2011
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
@@ -5804,7 +5807,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.5.6rc02 - October 26, 2011:
+Libpng version 1.5.6rc02 - October 27, 2011:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -5827,7 +5830,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.5.6rc02, October 26, 2011, are
+libpng versions 1.2.6, August 15, 2004, through 1.5.6rc02, October 27, 2011, are
 Copyright (c) 2004,2006-2007 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -5926,7 +5929,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-October 26, 2011
+October 27, 2011
 
 .\" end of man page
 
diff --git a/pngrutil.c b/pngrutil.c
index 47b752b29..374dfeb69 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -3419,7 +3419,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
 
             for (i = 0; i < row_info->width; i++)
             {
-               png_byte v = (png_byte)((*sp >> sshift) & 0xf);
+               png_byte v = (png_byte)((*sp >> sshift) & 0x0f);
                int j;
 
                for (j = 0; j < jstop; j++)
@@ -3979,11 +3979,11 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
       */
      {
         png_bytep temp = png_ptr->big_row_buf + 32;
-        int extra = (int)((temp - (png_bytep)0) & 0xf);
+        int extra = (int)((temp - (png_bytep)0) & 0x0f);
         png_ptr->row_buf = temp - extra - 1/*filter byte*/;
 
         temp = png_ptr->big_prev_row + 32;
-        extra = (int)((temp - (png_bytep)0) & 0xf);
+        extra = (int)((temp - (png_bytep)0) & 0x0f);
         png_ptr->prev_row = temp - extra - 1/*filter byte*/;
      }