diff --git a/bin/autoconf b/bin/autoconf
index 90e1822..3b58d1f 100755
--- a/bin/autoconf
+++ b/bin/autoconf
@@ -19,6 +19,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.

+PREFIX="$(cd "$(dirname "$0")/.." && pwd)"
+
 ## -------------------- ##
 ## M4sh Initialization. ##
 ## -------------------- ##
diff --git a/bin/autoheader b/bin/autoheader
index 2994b69..4cd2587 100755
--- a/bin/autoheader
+++ b/bin/autoheader
@@ -29,9 +29,14 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, "$pkgdatadir";

diff --git a/bin/autom4te b/bin/autom4te
index 215c42a..2a9e9ea 100755
--- a/bin/autom4te
+++ b/bin/autom4te
@@ -25,9 +25,14 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, $pkgdatadir;

@@ -393,6 +398,9 @@ Try '$me --help' for more information."
   $tcache = "$cache/traces.";
   $ocache = "$cache/output.";

+  # added by tea
+  @prepend_include = map { $_ =~ s/\$PREFIX/$prefix/r } @prepend_include;
+
   # Normalize the includes: the first occurrence is enough, several is
   # a pain since it introduces a useless difference in the path which
   # invalidates the cache.  And strip '.' which is implicit and always
diff --git a/bin/autoreconf b/bin/autoreconf
index 69c27ea..96d3ab9 100755
--- a/bin/autoreconf
+++ b/bin/autoreconf
@@ -28,10 +28,15 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 my $buildauxdir;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, $pkgdatadir;

diff --git a/bin/autoscan b/bin/autoscan
index b41d9f3..815bb7c 100755
--- a/bin/autoscan
+++ b/bin/autoscan
@@ -27,9 +27,14 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, $pkgdatadir;

diff --git a/bin/autoupdate b/bin/autoupdate
index 156d508..e31c5d1 100755
--- a/bin/autoupdate
+++ b/bin/autoupdate
@@ -28,9 +28,14 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, $pkgdatadir;

diff --git a/bin/ifnames b/bin/ifnames
index c5823fc..3177eb0 100755
--- a/bin/ifnames
+++ b/bin/ifnames
@@ -32,9 +32,14 @@ eval 'case $# in 0) exec perl -S "$0";; *) exec perl
 use 5.006;
 use strict;
 use warnings FATAL => 'all';
+use Cwd qw(abs_path);
+use File::Basename;

+my $prefix;
 BEGIN
 {
+  $prefix = dirname(dirname(abs_path(__FILE__)));
+
   my $pkgdatadir = $ENV{'autom4te_perllibdir'} || $prefix.'/share/autoconf';
   unshift @INC, $pkgdatadir;

diff --git a/bin/autom4te b/bin/autom4te
 index 042ece6..89e4968 100755
 --- a/bin/autom4te
 +++ b/bin/autom4te
 @@ -393,6 +393,9 @@ Try '$me --help' for more information."
    $tcache = "$cache/traces.";
    $ocache = "$cache/output.";

 +  # added by tea
 +  @prepend_include = map { $_ =~ s/\$PREFIX/$prefix/r } @prepend_include;
 +
    # Normalize the includes: the first occurrence is enough, several is
    # a pain since it introduces a useless difference in the path which
    # invalidates the cache.  And strip '.' which is implicit and always