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diff --git a/contrib/perl5/lib/Tie/Hash.pm b/contrib/perl5/lib/Tie/Hash.pm
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+++ b/contrib/perl5/lib/Tie/Hash.pm
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+package Tie::Hash;
+
+=head1 NAME
+
+Tie::Hash, Tie::StdHash - base class definitions for tied hashes
+
+=head1 SYNOPSIS
+
+    package NewHash;
+    require Tie::Hash;
+    
+    @ISA = (Tie::Hash);
+    
+    sub DELETE { ... }		# Provides needed method
+    sub CLEAR { ... }		# Overrides inherited method
+    
+    
+    package NewStdHash;
+    require Tie::Hash;
+    
+    @ISA = (Tie::StdHash);
+    
+    # All methods provided by default, define only those needing overrides
+    sub DELETE { ... }
+    
+    
+    package main;
+    
+    tie %new_hash, 'NewHash';
+    tie %new_std_hash, 'NewStdHash';
+
+=head1 DESCRIPTION
+
+This module provides some skeletal methods for hash-tying classes. See
+L<perltie> for a list of the functions required in order to tie a hash
+to a package. The basic B<Tie::Hash> package provides a C<new> method, as well
+as methods C<TIEHASH>, C<EXISTS> and C<CLEAR>. The B<Tie::StdHash> package
+provides most methods required for hashes in L<perltie>. It inherits from
+B<Tie::Hash>, and causes tied hashes to behave exactly like standard hashes,
+allowing for selective overloading of methods. The C<new> method is provided
+as grandfathering in the case a class forgets to include a C<TIEHASH> method.
+
+For developers wishing to write their own tied hashes, the required methods
+are briefly defined below. See the L<perltie> section for more detailed
+descriptive, as well as example code:
+
+=over
+
+=item TIEHASH classname, LIST
+
+The method invoked by the command C<tie %hash, classname>. Associates a new
+hash instance with the specified class. C<LIST> would represent additional
+arguments (along the lines of L<AnyDBM_File> and compatriots) needed to
+complete the association.
+
+=item STORE this, key, value
+
+Store datum I<value> into I<key> for the tied hash I<this>.
+
+=item FETCH this, key
+
+Retrieve the datum in I<key> for the tied hash I<this>.
+
+=item FIRSTKEY this
+
+Return the (key, value) pair for the first key in the hash.
+
+=item NEXTKEY this, lastkey
+
+Return the next key for the hash.
+
+=item EXISTS this, key
+
+Verify that I<key> exists with the tied hash I<this>.
+
+=item DELETE this, key
+
+Delete the key I<key> from the tied hash I<this>.
+
+=item CLEAR this
+
+Clear all values from the tied hash I<this>.
+
+=back
+
+=head1 CAVEATS
+
+The L<perltie> documentation includes a method called C<DESTROY> as
+a necessary method for tied hashes. Neither B<Tie::Hash> nor B<Tie::StdHash>
+define a default for this method. This is a standard for class packages,
+but may be omitted in favor of a simple default.
+
+=head1 MORE INFORMATION
+
+The packages relating to various DBM-related implemetations (F<DB_File>,
+F<NDBM_File>, etc.) show examples of general tied hashes, as does the
+L<Config> module. While these do not utilize B<Tie::Hash>, they serve as
+good working examples.
+
+=cut
+
+use Carp;
+
+sub new {
+    my $pkg = shift;
+    $pkg->TIEHASH(@_);
+}
+
+# Grandfather "new"
+
+sub TIEHASH {
+    my $pkg = shift;
+    if (defined &{"${pkg}::new"}) {
+	carp "WARNING: calling ${pkg}->new since ${pkg}->TIEHASH is missing"
+	    if $^W;
+	$pkg->new(@_);
+    }
+    else {
+	croak "$pkg doesn't define a TIEHASH method";
+    }
+}
+
+sub EXISTS {
+    my $pkg = ref $_[0];
+    croak "$pkg doesn't define an EXISTS method";
+}
+
+sub CLEAR {
+    my $self = shift;
+    my $key = $self->FIRSTKEY(@_);
+    my @keys;
+
+    while (defined $key) {
+	push @keys, $key;
+	$key = $self->NEXTKEY(@_, $key);
+    }
+    foreach $key (@keys) {
+	$self->DELETE(@_, $key);
+    }
+}
+
+# The Tie::StdHash package implements standard perl hash behaviour.
+# It exists to act as a base class for classes which only wish to
+# alter some parts of their behaviour.
+
+package Tie::StdHash;
+@ISA = qw(Tie::Hash);
+
+sub TIEHASH  { bless {}, $_[0] }
+sub STORE    { $_[0]->{$_[1]} = $_[2] }
+sub FETCH    { $_[0]->{$_[1]} }
+sub FIRSTKEY { my $a = scalar keys %{$_[0]}; each %{$_[0]} }
+sub NEXTKEY  { each %{$_[0]} }
+sub EXISTS   { exists $_[0]->{$_[1]} }
+sub DELETE   { delete $_[0]->{$_[1]} }
+sub CLEAR    { %{$_[0]} = () }
+
+1;