diff --git a/src/tools/copyright b/src/tools/copyright
deleted file mode 100755
index b0d61e1..0000000
--- a/src/tools/copyright
+++ /dev/null
@@ -1,14 +0,0 @@
-#!/bin/sh
-
-# src/tools/copyright
-
-echo "Using current year:  `date '+%Y'`"
-
-rgrep -l 'Copyright.*PostgreSQL Global Development Group' | while read FILE
-do
-	pipe sed 's/^\(.*Copyright (c) [12][0-9][0-9][0-9]\) \?- \?[12][0-9][0-9][0-9] \?,\?\( PostgreSQL Global Development Group.*\)$/\1-'`date '+%Y'`',\2/' $FILE
-	# handle cases where only one year appears
-	pipe sed 's/^\(.*Copyright (c) [12][0-9][0-9][0-9]\) \?,\?\( PostgreSQL Global Development Group.*\)$/\1-'`date '+%Y'`',\2/' $FILE
-done
-
-echo "Manually update doc/src/sgml/legal.sgml and src/interfaces/libpq/libpq.rc.in too" 1>&2
diff --git a/src/tools/copyright.pl b/src/tools/copyright.pl
new file mode 100755
index 0000000..d981911
--- /dev/null
+++ b/src/tools/copyright.pl
@@ -0,0 +1,43 @@
+#!/usr/bin/perl 
+#################################################################
+# copyright.pl -- update copyright notices throughout the source tree, idempotently.
+#
+# Copyright (c) 2011, PostgreSQL Global Development Group
+#
+# src/tools/copyright.pl
+#################################################################
+
+use strict;
+use warnings;
+
+use File::Find;
+
+my $pgdg = 'PostgreSQL Global Development Group';
+my $cc = 'Copyright (c) ';
+# year-1900 is what localtime(time) puts in element 5
+my $year = 1900+${[localtime(time)]}[5];
+
+print "Using current year:  $year\n";
+
+find({wanted => \&wanted, no_chdir => 1}, '.');
+
+sub wanted {
+    return unless -f $File::Find::name;
+
+    my @lines;
+    tie @lines, Tie::File, $File::Find::name;
+
+    foreach my $line (@lines) {
+        # We only care about lines with a copyright notice.
+        next unless $line =~ m/$cc.*$pgdg/;
+        # We stop when we've done one substitution.  This is both for
+        # efficiency and, at least in the case of this program, for
+        # correctness.
+        last if $line =~ m/$cc.*$year.*$pgdg/;
+        last if $line =~ s/($cc\d{4})(, $pgdg)/$1-$year$2/;
+        last if $line =~ s/($cc\d{4})-\d{4}(, $pgdg)/$1-$year$2/;
+    }
+    untie @lines;
+}
+print "Manually update doc/src/sgml/legal.sgml and src/interfaces/libpq/libpq.rc.in too\n";
+