diff --git a/ANNOUNCE b/ANNOUNCE
index 2906714bd..625ca958e 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.4.6beta01 - December 27, 2010
+Libpng 1.4.6beta01 - December 29, 2010
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -16,74 +16,20 @@ Source files with LF line endings (for Unix/Linux) and with a
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
+   lp146b01.7z (LZMA-compressed, recommended)
    lp146b01.zip
-   lp146b01.7z
 
 Other information:
 
    1.4.6beta01-README.txt
    1.4.6beta01-LICENSE.txt
 
-Changes since the last public release (1.4.4):
+Changes since the last public release (1.4.5):
 
-version 1.4.5beta01 [September 25, 2010]
-  Fixed possible configure.ac bug introduced in version 1.4.4rc05.
-  Rebuilt configure scripts with autoconf-2.68 instead of autoconf-2.65
-
-version 1.4.5beta02 [October 5, 2010]
-  Reverted configure scripts to autoconf-2.65
-  Fixed problem with symbols creation in Makefile.am which was assuming that
-    all versions of cpp write to standard output by default (Martin Banky). The
-    bug was introduced in libpng-1.2.9beta5.
-
-version 1.4.5beta03 [October 8, 2010]
-  Wrapped long lines in CMakeLists.txt and introduced ${libpng_public_hdrs}
-  Undid Makefile.am revision of 1.4.5beta02.
-
-version 1.4.5beta04 [November 8, 2010]
-  Check for out-of-range text compression mode in png_set_text().
-
-version 1.4.5rc01 [November 19, 2010]
-  No changes.
-
-version 1.4.5beta05 [December 27, 2010]
-  Removed some extraneous parentheses that appeared in pngrutil.c of
-    libpng-1.4.3beta01
-  Revised png_get_uint_32, png_get_int_32, png_get_uint_16 (Cosmin)
-  Moved reading of file signature into png_read_sig (Cosmin)
-  Fixed atomicity of chunk header serialization (Cosmin)
-  Added test for io_state in pngtest.c (Cosmin)
-  Added "#!/bin/sh" at the top of contrib/pngminim/*/gather.sh scripts.
-
-version 1.4.5beta06 [November 21, 2010]
-  Restored the parentheses in pngrutil.c; they are needed when the
-    png_get_*int_*() functions are compiled (i.e., when PNG_USE_READ_MACROS
-    is not defined).
-  Make the "png_get_uint_16" macro return a png_uint_32 in libpng-1.4 for API
-    compatibility.
-  Changes to remove gcc warnings (John Bowler)
-    Certain optional gcc warning flags resulted in warnings in libpng code.
-    With these changes only -Wconversion and -Wcast-qual cannot be turned on.
-    Changes are trivial rearrangements of code.  -Wconversion is not possible
-    for pngrutil.c (because of the widespread use of += et al on variables
-    smaller than (int) or (unsigned int)) and -Wcast-qual is not possible
-    with pngwio.c and pngwutil.c because the 'write' callback and zlib
-    compression both fail to declare their input buffers with 'const'.
-
-version 1.4.5beta07 [November 25, 2010]
-  Reverted png_get_uint_16 macro to beta05 and added comment about the
-    potential API incompatibility.
-
-version 1.4.5rc02 [December 2, 2010]
-  No changes.
-
-version 1.4.5rc03 [December 3, 2010]
-  Added missing vstudio/*/*.vcxproj files to the zip and 7z distributions.
-
-version 1.4.5 [December 9, 2010]
-  Removed PNG_NO_WRITE_GAMMA from pngminim/encoder/pngusr.h
-
-version 1.4.5beta01 [December 27, 2010]
+Version 1.4.6beta01 [December 29, 2010]
+  Fixed bug in background transformation handling in pngrtran.c (it was
+    looking for the flag in png_ptr->transformations instead of in
+    png_ptr->flags).
 
 Send comments/corrections/commendations to glennrp at users.sourceforge.net
 or to png-mng-implement at lists.sf.net (subscription required; visit
diff --git a/CHANGES b/CHANGES
index 477437088..9dd5cc656 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2735,7 +2735,10 @@ version 1.4.5rc03 [December 3, 2010]
 version 1.4.5 [December 9, 2010]
   Removed PNG_NO_WRITE_GAMMA from pngminim/encoder/pngusr.h
 
-version 1.4.5beta01 [December 27, 2010]
+version 1.4.6beta01 [December 29, 2010]
+  Fixed bug in background transformation handling in pngrtran.c (it was
+    looking for the flag in png_ptr->transformations instead of in
+    png_ptr->flags).
 
 Send comments/corrections/commendations to glennrp at users.sourceforge.net
 or to png-mng-implement at lists.sf.net (subscription required; visit
diff --git a/pngrtran.c b/pngrtran.c
index ebfaad16e..2c3d4a999 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.4.5 [December 27, 2010]
+ * Last changed in libpng 1.4.5 [December 29, 2010]
  * Copyright (c) 1998-2010 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -1008,7 +1008,7 @@ png_init_read_transformations(png_structp png_ptr)
              */
             png_ptr->transformations &= ~PNG_BACKGROUND;
             png_ptr->transformations &= ~PNG_GAMMA;
-            png_ptr->transformations |= PNG_STRIP_ALPHA;
+            png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
          }
          /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */
          else
@@ -1131,7 +1131,7 @@ png_init_read_transformations(png_structp png_ptr)
 
       /* Handled alpha, still need to strip the channel. */
       png_ptr->transformations &= ~PNG_BACKGROUND;
-      png_ptr->transformations |= PNG_STRIP_ALPHA;
+      png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
    }
 #endif /* PNG_READ_BACKGROUND_SUPPORTED */