First try.

scripts/update-copyright

+#!/bin/bash
+# $Id: update-copyright,v 1.1 1994/04/05 07:49:23 ceder Exp $
+# Copyright (C) 1994  Lysator Academic Computer Association.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+# Please mail bug reports to bug-lyskom@lysator.liu.se.
+set -e
+while read file
+do
+    grep 'Copyright' $file \
+	| tr , '\012' \
+	| sed -n 's/.*\([0-9][0-9][0-9][0-9]\).*/\1/p' > /tmp/$$.year
+    cvs log $file \
+	| sed -n 's/^date: \([0-9][0-9][0-9][0-9]\).*author.*state.*$/\1/p' \
+	| sort | uniq >> /tmp/$$.year
+    y=`sort /tmp/$$.year | uniq \
+	| (read first ; echo -n $first; \
+	   while read second; do echo -n ", $second"; done)`
+    sed 's/\(Copyright[^0-9]*\)[0-9 ,]*[0-9]\([^0-9]*\)/\1'"$y"'\2/' \
+	< $file > /tmp/$$.file
+    mv /tmp/$$.file $file
+done