diff --git a/configure b/configure
index cd087df80..033cb4d48 100755
--- a/configure
+++ b/configure
@@ -750,6 +750,7 @@ SELINUX_USAGE
 BSDAUTH_USAGE
 DONT_LEAK_PATH_INFO
 INSTALL_NOEXEC
+INSTALL_BACKUP
 sesh_file
 noexec_file
 NOEXECDIR
@@ -2847,6 +2848,7 @@ $as_echo "$as_me: Configuring Sudo version $PACKAGE_VERSION" >&6;}
 
 
 
+
 
 
 #
@@ -2896,6 +2898,7 @@ PLUGINDIR=/usr/local/libexec/sudo
 #
 # End initial values for man page substitution
 #
+INSTALL_BACKUP=
 INSTALL_NOEXEC=
 exampledir='$(docdir)/examples'
 devdir='$(srcdir)'
@@ -14908,6 +14911,9 @@ _ACEOF
 		# Load time is much greater if writable so use 0555.
 		SHLIB_MODE=0555
 
+		# HP-UX won't unlink a shared lib that is open
+		INSTALL_BACKUP='~'
+
 		for ac_func in pstat_getproc
 do :
   ac_fn_c_check_func "$LINENO" "pstat_getproc" "ac_cv_func_pstat_getproc"
@@ -14940,6 +14946,9 @@ done
 		# Load time is much greater if writable so use 0555.
 		SHLIB_MODE=0555
 
+		# HP-UX won't unlink a shared lib that is open
+		INSTALL_BACKUP='~'
+
 		# The HP bundled compiler cannot generate shared libs
 		if test -z "$GCC"; then
 		    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for HP bundled C compiler" >&5
diff --git a/configure.ac b/configure.ac
index abae6df9b..d64e3c501 100644
--- a/configure.ac
+++ b/configure.ac
@@ -63,6 +63,7 @@ AC_SUBST([NOEXECFILE])
 AC_SUBST([NOEXECDIR])
 AC_SUBST([noexec_file])
 AC_SUBST([sesh_file])
+AC_SUBST([INSTALL_BACKUP])
 AC_SUBST([INSTALL_NOEXEC])
 AC_SUBST([DONT_LEAK_PATH_INFO])
 AC_SUBST([BSDAUTH_USAGE])
@@ -186,6 +187,7 @@ dnl
 dnl Initial values for Makefile variables listed above
 dnl May be overridden by environment variables..
 dnl
+INSTALL_BACKUP=
 INSTALL_NOEXEC=
 exampledir='$(docdir)/examples'
 devdir='$(srcdir)'
@@ -1779,6 +1781,9 @@ case "$host" in
 		# Load time is much greater if writable so use 0555.
 		SHLIB_MODE=0555
 
+		# HP-UX won't unlink a shared lib that is open
+		INSTALL_BACKUP='~'
+
 		AC_CHECK_FUNCS([pstat_getproc])
 		;;
     *-*-hpux*)
@@ -1800,6 +1805,9 @@ case "$host" in
 		# Load time is much greater if writable so use 0555.
 		SHLIB_MODE=0555
 
+		# HP-UX won't unlink a shared lib that is open
+		INSTALL_BACKUP='~'
+
 		# The HP bundled compiler cannot generate shared libs
 		if test -z "$GCC"; then
 		    AC_CACHE_CHECK([for HP bundled C compiler],
diff --git a/lib/util/Makefile.in b/lib/util/Makefile.in
index 1a5116653..59a581bed 100644
--- a/lib/util/Makefile.in
+++ b/lib/util/Makefile.in
@@ -52,6 +52,7 @@ AWK = @AWK@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # C preprocessor defines
 CPPDEFS = -D_PATH_SUDO_CONF=\"$(sysconfdir)/sudo.conf\"
@@ -211,7 +212,7 @@ install: install-dirs
 	case "$(LT_LDFLAGS)" in \
 	*-no-install*) ;; \
 	*)  if [ X"$(shlib_enable)" = X"yes" ]; then \
-		INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --quiet --mode=install $(INSTALL) $(INSTALL_OWNER) libsudo_util.la $(DESTDIR)$(libexecdir)/sudo; \
+		INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --quiet --mode=install $(INSTALL) $(INSTALL_OWNER) libsudo_util.la $(DESTDIR)$(libexecdir)/sudo; \
 	    fi;; \
 	esac
 
diff --git a/lib/zlib/Makefile.in b/lib/zlib/Makefile.in
index 5bf82ff59..22f6601d6 100644
--- a/lib/zlib/Makefile.in
+++ b/lib/zlib/Makefile.in
@@ -50,6 +50,7 @@ AWK = @AWK@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # C preprocessor flags
 CPPFLAGS = -I. -I$(srcdir)
@@ -117,7 +118,7 @@ install:
 	case "$(LT_LDFLAGS)" in \
 	*-no-install*) ;; \
 	*)  if [ X"$(shlib_enable)" = X"yes" ]; then \
-		INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --quiet --mode=install $(INSTALL) $(INSTALL_OWNER) libsudo_z.la $(DESTDIR)$(libexecdir)/sudo; \
+		INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --quiet --mode=install $(INSTALL) $(INSTALL_OWNER) libsudo_z.la $(DESTDIR)$(libexecdir)/sudo; \
 	    fi;; \
 	esac
 
diff --git a/plugins/group_file/Makefile.in b/plugins/group_file/Makefile.in
index d256e20d6..fddb90e80 100644
--- a/plugins/group_file/Makefile.in
+++ b/plugins/group_file/Makefile.in
@@ -35,6 +35,7 @@ AWK = @AWK@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # Libraries
 LT_LIBS = $(top_builddir)/lib/util/libsudo_util.la
@@ -133,7 +134,7 @@ install-doc:
 
 install-plugin: install-dirs group_file.la
 	if [ X"$(shlib_enable)" = X"yes" ]; then \
-	    INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) group_file.la $(DESTDIR)$(plugindir); \
+	    INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) group_file.la $(DESTDIR)$(plugindir); \
 	fi
 
 uninstall:
diff --git a/plugins/sample/Makefile.in b/plugins/sample/Makefile.in
index 1c339e63b..4230bd696 100644
--- a/plugins/sample/Makefile.in
+++ b/plugins/sample/Makefile.in
@@ -35,6 +35,7 @@ AWK = @AWK@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # Libraries
 LIBS = $(top_builddir)/lib/util/libsudo_util.la
@@ -132,7 +133,7 @@ install-doc:
 
 install-plugin: install-dirs sample_plugin.la
 	if [ X"$(shlib_enable)" = X"yes" ]; then \
-	    INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sample_plugin.la $(DESTDIR)$(plugindir); \
+	    INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sample_plugin.la $(DESTDIR)$(plugindir); \
 	fi
 
 uninstall:
diff --git a/plugins/sudoers/Makefile.in b/plugins/sudoers/Makefile.in
index 0bff3af09..7f2c96e2c 100644
--- a/plugins/sudoers/Makefile.in
+++ b/plugins/sudoers/Makefile.in
@@ -48,6 +48,7 @@ PERL = perl
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # Libraries
 LT_LIBS = $(top_builddir)/lib/util/libsudo_util.la
@@ -320,8 +321,8 @@ install-dirs:
 	$(INSTALL) -d $(INSTALL_OWNER) -m 0700 $(DESTDIR)$(vardir)/lectured
 
 install-binaries: visudo sudoreplay install-dirs
-	INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 sudoreplay $(DESTDIR)$(replaydir)/sudoreplay
-	INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 visudo $(DESTDIR)$(visudodir)/visudo
+	INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 sudoreplay $(DESTDIR)$(replaydir)/sudoreplay
+	INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 visudo $(DESTDIR)$(visudodir)/visudo
 
 install-includes:
 
@@ -332,7 +333,7 @@ install-plugin: sudoers.la install-dirs
 	case "$(LT_LDFLAGS)" in \
 	*-no-install*) ;; \
 	*)  if [ X"$(shlib_enable)" = X"yes" ]; then \
-		INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sudoers.la $(DESTDIR)$(plugindir); \
+		INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sudoers.la $(DESTDIR)$(plugindir); \
 	    fi;; \
 	esac
 
diff --git a/plugins/system_group/Makefile.in b/plugins/system_group/Makefile.in
index af64ee5d5..1635d3b42 100644
--- a/plugins/system_group/Makefile.in
+++ b/plugins/system_group/Makefile.in
@@ -35,6 +35,7 @@ AWK = @AWK@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # Libraries
 LT_LIBS = $(top_builddir)/lib/util/libsudo_util.la
@@ -133,7 +134,7 @@ install-doc:
 
 install-plugin: install-dirs system_group.la
 	if [ X"$(shlib_enable)" = X"yes" ]; then \
-	    INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) system_group.la $(DESTDIR)$(plugindir); \
+	    INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) system_group.la $(DESTDIR)$(plugindir); \
 	fi
 
 uninstall:
diff --git a/src/Makefile.in b/src/Makefile.in
index 3a9b9e586..8f2c45860 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -35,6 +35,7 @@ SED = @SED@
 # Our install program supports extra flags...
 INSTALL = $(SHELL) $(top_srcdir)/install-sh -c
 INSTALL_OWNER = -o $(install_uid) -g $(install_gid)
+INSTALL_BACKUP = @INSTALL_BACKUP@
 
 # Libraries
 LT_LIBS = $(top_builddir)/lib/util/libsudo_util.la
@@ -174,11 +175,11 @@ install-rc: install-dirs
 	fi
 
 install-binaries: install-dirs $(PROGS)
-	INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 04755 sudo $(DESTDIR)$(bindir)/sudo
+	INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 04755 sudo $(DESTDIR)$(bindir)/sudo
 	rm -f $(DESTDIR)$(bindir)/sudoedit
 	ln -s sudo $(DESTDIR)$(bindir)/sudoedit
 	if [ -f sesh ]; then \
-	    INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 sesh $(DESTDIR)$(libexecdir)/sudo/sesh; \
+	    INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m 0755 sesh $(DESTDIR)$(libexecdir)/sudo/sesh; \
 	fi
 
 install-doc:
@@ -186,7 +187,7 @@ install-doc:
 install-includes:
 
 install-noexec: install-dirs sudo_noexec.la
-	INSTALL_BACKUP='~' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sudo_noexec.la $(DESTDIR)$(noexecdir)
+	INSTALL_BACKUP='$(INSTALL_BACKUP)' $(LIBTOOL) $(LTFLAGS) --mode=install $(INSTALL) $(INSTALL_OWNER) -m $(shlib_mode) sudo_noexec.la $(DESTDIR)$(noexecdir)
 
 install-plugin: