--- lib/books/coupled/Makefile.am
+++ lib/books/coupled/Makefile.am
@@ -1,3 +1,3 @@
 ## Process this file with automake to produce Makefile.in
 
-EXTRA_DIST = res_books_stereo.h res_books_51.h
+EXTRA_DIST = res_books_stereo.h
--- lib/books/coupled/Makefile.in
+++ lib/books/coupled/Makefile.in
@@ -265,7 +265,7 @@
 top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
-EXTRA_DIST = res_books_stereo.h res_books_51.h
+EXTRA_DIST = res_books_stereo.h
 all: all-am
 
 .SUFFIXES:
--- lib/modes/Makefile.am
+++ lib/modes/Makefile.am
@@ -3,4 +3,4 @@
 EXTRA_DIST = floor_all.h psych_44.h residue_44.h setup_11.h setup_32.h \
 	     setup_8.h psych_11.h psych_8.h residue_44u.h setup_16.h \
 	     setup_44.h setup_X.h psych_16.h residue_16.h residue_8.h \
-	     setup_22.h setup_44u.h setup_44p51.h residue_44p51.h
+	     setup_22.h setup_44u.h
--- lib/modes/Makefile.in
+++ lib/modes/Makefile.in
@@ -268,7 +268,7 @@
 EXTRA_DIST = floor_all.h psych_44.h residue_44.h setup_11.h setup_32.h \
 	     setup_8.h psych_11.h psych_8.h residue_44u.h setup_16.h \
 	     setup_44.h setup_X.h psych_16.h residue_16.h residue_8.h \
-	     setup_22.h setup_44u.h setup_44p51.h residue_44p51.h
+	     setup_22.h setup_44u.h
 
 all: all-am
 
--- lib/vorbisenc.c
+++ lib/vorbisenc.c
@@ -154,7 +154,6 @@
 
 #include "modes/setup_44.h"
 #include "modes/setup_44u.h"
-#include "modes/setup_44p51.h"
 #include "modes/setup_32.h"
 #include "modes/setup_8.h"
 #include "modes/setup_11.h"
@@ -164,7 +163,6 @@
 
 static const ve_setup_data_template *const setup_list[]={
   &ve_setup_44_stereo,
-  &ve_setup_44_51,
   &ve_setup_44_uncoupled,
 
   &ve_setup_32_stereo,