diff --git a/contrib/gregbook/readpng2.c b/contrib/gregbook/readpng2.c
index 2ee6b68..eb53030 100644
--- a/contrib/gregbook/readpng2.c
+++ b/contrib/gregbook/readpng2.c
@@ -73,84 +73,10 @@
 
 void readpng2_version_info(void)
 {
-#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && \
-    (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \
-    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-    /*
-     * WARNING:  This preprocessor approach means that the following code
-     *           cannot be used with a libpng DLL older than 1.2.0--the
-     *           compiled-in symbols for the new functions will not exist.
-     *           (Could use dlopen() and dlsym() on Unix and corresponding
-     *           calls for Windows, but not portable...)
-     */
-    {
-        int mmxsupport = png_mmx_support();
-        if (mmxsupport < 0)
-            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-              "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
-        else {
-            int compilerID;
-            png_uint_32 mmx_mask = png_get_mmx_flagmask(
-              PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
 
-            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-              "with MMX support\n   (%s version).", PNG_LIBPNG_VER_STRING,
-              png_libpng_ver, compilerID == 1? "MSVC++" :
-              (compilerID == 2? "GNU C" : "unknown"));
-            fprintf(stderr, "  Processor (x86%s) %s MMX instructions.\n",
-#if defined(__x86_64__)
-              "_64",
-#else
-              "",
-#endif
-              mmxsupport? "supports" : "does not support");
-            if (mmxsupport > 0) {
-                int num_optims = 0;
-
-                fprintf(stderr,
-                  "      Potential MMX optimizations supported by libpng:\n");
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_UP)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)
-                    ++num_optims;
-                if (num_optims)
-                    fprintf(stderr,
-                      "         decoding %s row filters (reading)\n",
-                      (num_optims == 4)? "all non-trivial" : "some");
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW) {
-                    fprintf(stderr, "         combining rows (reading)\n");
-                    ++num_optims;
-                }
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_INTERLACE) {
-                    fprintf(stderr,
-                      "         expanding interlacing (reading)\n");
-                    ++num_optims;
-                }
-                mmx_mask &= ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-                             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
-                if (mmx_mask) {
-                    fprintf(stderr, "         other (unknown)\n");
-                    ++num_optims;
-                }
-                if (num_optims == 0)
-                    fprintf(stderr, "         (none)\n");
-            }
-        }
-    }
-#else
-    fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-      "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
-#endif
-
-    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    fprintf(stderr, "   and with zlib %s; using zlib %s.\n",
       ZLIB_VERSION, zlib_version);
 }
 
@@ -242,96 +168,6 @@
       readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
 
 
-    /*
-     * may as well enable or disable MMX routines here, if supported;
-     *
-     * to enable all:  mask = png_get_mmx_flagmask (
-     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
-     *                 flags = png_get_asm_flags (png_ptr);
-     *                 flags |= mask;
-     *                 png_set_asm_flags (png_ptr, flags);
-     *
-     * to disable all:  mask = png_get_mmx_flagmask (
-     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
-     *                  flags = png_get_asm_flags (png_ptr);
-     *                  flags &= ~mask;
-     *                  png_set_asm_flags (png_ptr, flags);
-     */
-
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \
-    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-    /*
-     * WARNING:  This preprocessor approach means that the following code
-     *           cannot be used with a libpng DLL older than 1.2.0--the
-     *           compiled-in symbols for the new functions will not exist.
-     *           (Could use dlopen() and dlsym() on Unix and corresponding
-     *           calls for Windows, but not portable...)
-     */
-    {
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-        png_uint_32 mmx_disable_mask = 0;
-        png_uint_32 asm_flags, mmx_mask;
-        int compilerID;
-
-        if (mainprog_ptr->nommxfilters)
-            mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
-        if (mainprog_ptr->nommxcombine)
-            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_COMBINE_ROW;
-        if (mainprog_ptr->nommxinterlace)
-            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_INTERLACE;
-        asm_flags = png_get_asm_flags(png_ptr);
-        png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
-
-
-        /* Now query libpng's asm settings, just for yuks.  Note that this
-         * differs from the querying of its *potential* MMX capabilities
-         * in readpng2_version_info(); this is true runtime verification. */
-
-        asm_flags = png_get_asm_flags(png_ptr);
-        mmx_mask = png_get_mmx_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE,
-          &compilerID);
-        if (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED)
-            fprintf(stderr,
-              "  MMX support (%s version) is compiled into libpng\n",
-              compilerID == 1? "MSVC++" :
-              (compilerID == 2? "GNU C" : "unknown"));
-        else
-            fprintf(stderr, "  MMX support is not compiled into libpng\n");
-        fprintf(stderr, "  MMX instructions are %ssupported by CPU\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU)? "" : "not ");
-        fprintf(stderr, "  MMX read support for combining rows is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)? "en" : "dis");
-        fprintf(stderr,
-          "  MMX read support for expanding interlacing is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_INTERLACE)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"sub\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"up\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"avg\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"Paeth\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)? "en" : "dis");
-        asm_flags &= (mmx_mask & ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-                                  | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ));
-        if (asm_flags)
-            fprintf(stderr,
-              "  additional MMX support is also enabled (0x%02lx)\n",
-              asm_flags);
-#else  /* !PNG_ASSEMBLER_CODE_SUPPORTED */
-        fprintf(stderr, "  MMX querying is disabled in libpng.\n");
-#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
-    }
-#endif
-
-
     /* make sure we save our pointers for use in readpng2_decode_data() */
 
     mainprog_ptr->png_ptr = png_ptr;
diff --git a/contrib/gregbook/readpng2.h b/contrib/gregbook/readpng2.h
index fbfffb4..6b3660d 100644
--- a/contrib/gregbook/readpng2.h
+++ b/contrib/gregbook/readpng2.h
@@ -96,11 +96,6 @@
     int rowbytes;
     int channels;
     int need_bgcolor;
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-    int nommxfilters;
-    int nommxcombine;
-    int nommxinterlace;
-#endif
     int state;
     uch bg_red;
     uch bg_green;
diff --git a/contrib/gregbook/rpng2-win.c b/contrib/gregbook/rpng2-win.c
index 9f7ad78..8c831db 100644
--- a/contrib/gregbook/rpng2-win.c
+++ b/contrib/gregbook/rpng2-win.c
@@ -32,6 +32,7 @@
     - 2.01:  fixed 64-bit typo in readpng2.c
     - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
               unexpected-EOF and file-read-error cases
+    - 2.03:  removed runtime MMX-enabling/disabling and obsolete -mmx* options
 
   ---------------------------------------------------------------------------
 
@@ -395,18 +396,6 @@
             }
         } else if (!strncmp(*argv, "-timing", 2)) {
             timing = TRUE;
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-        } else if (!strncmp(*argv, "-nommxfilters", 7)) {
-            rpng2_info.nommxfilters = TRUE;
-        } else if (!strncmp(*argv, "-nommxcombine", 7)) {
-            rpng2_info.nommxcombine = TRUE;
-        } else if (!strncmp(*argv, "-nommxinterlace", 7)) {
-            rpng2_info.nommxinterlace = TRUE;
-        } else if (!strcmp(*argv, "-nommx")) {
-            rpng2_info.nommxfilters = TRUE;
-            rpng2_info.nommxcombine = TRUE;
-            rpng2_info.nommxinterlace = TRUE;
-#endif
         } else {
             if (**argv != '-') {
                 filename = *argv;
@@ -430,9 +419,6 @@
         readpng2_version_info();
         fprintf(stderr, "\n"
           "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-          "        %*s [[-nommxfilters] [-nommxcombine] [-nommxinterlace] | -nommx]\n"
-#endif
           "        %*s file.png\n\n"
           "    exp \ttransfer-function exponent (``gamma'') of the display\n"
           "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
@@ -445,10 +431,6 @@
           "\t\t  transparent images; overrides -bgcolor option\n"
           "    -timing\tenables delay for every block read, to simulate modem\n"
           "\t\t  download of image (~36 Kbps)\n"
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-          "    -nommx*\tdisable optimized MMX routines for decoding row filters,\n"
-          "\t\t  combining rows, and expanding interlacing, respectively\n"
-#endif
           "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
           "Press Q or Esc to quit this usage screen. ",
           PROGNAME,
diff --git a/contrib/gregbook/rpng2-x.c b/contrib/gregbook/rpng2-x.c
index 873af23..238ec0b 100644
--- a/contrib/gregbook/rpng2-x.c
+++ b/contrib/gregbook/rpng2-x.c
@@ -40,6 +40,7 @@
     - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
               unexpected-EOF and file-read-error cases; fixed Trace() cut-and-
               paste bugs
+    - 2.03:  deleted runtime MMX-enabling/disabling and obsolete -mmx* options
 
   ---------------------------------------------------------------------------
 
@@ -94,7 +95,7 @@
 
 #define PROGNAME  "rpng2-x"
 #define LONGNAME  "Progressive PNG Viewer for X"
-#define VERSION   "2.02 of 16 March 2008"
+#define VERSION   "2.03 of 25 February 2010"
 #define RESNAME   "rpng2"	/* our X resource application name */
 #define RESCLASS  "Rpng"	/* our X resource class name */
 
@@ -435,18 +436,6 @@
                     loop_interval = 100000;
             }
 #endif
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-        } else if (!strncmp(*argv, "-nommxfilters", 7)) {
-            rpng2_info.nommxfilters = TRUE;
-        } else if (!strncmp(*argv, "-nommxcombine", 7)) {
-            rpng2_info.nommxcombine = TRUE;
-        } else if (!strncmp(*argv, "-nommxinterlace", 7)) {
-            rpng2_info.nommxinterlace = TRUE;
-        } else if (!strcmp(*argv, "-nommx")) {
-            rpng2_info.nommxfilters = TRUE;
-            rpng2_info.nommxcombine = TRUE;
-            rpng2_info.nommxinterlace = TRUE;
-#endif
         } else {
             if (**argv != '-') {
                 filename = *argv;
@@ -468,9 +457,6 @@
         readpng2_version_info();
         fprintf(stderr, "\n"
           "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg | -bgpat pat]\n"
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-          "        %*s [[-nommxfilters] [-nommxcombine] [-nommxinterlace] | -nommx]\n"
-#endif
 #ifdef FEATURE_LOOP
           "        %*s [-usleep dur | -timing] [-pause] [-loop [sec]] file.png\n\n"
 #else
@@ -491,10 +477,6 @@
           "\t\t  is complete (depends on -bgpat)\n"
           "    sec \tseconds to display each background image (default = 2)\n"
 #endif
-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__))
-          "    -nommx*\tdisable optimized MMX routines for decoding row filters,\n"
-          "\t\t  combining rows, and expanding interlacing, respectively\n"
-#endif
           "    dur \tduration in microseconds to wait after displaying each\n"
           "\t\t  row (for demo purposes)\n"
           "    -timing\tenables delay for every block read, to simulate modem\n"