Add license.
diff --git a/builds/unix/configure.ac b/builds/unix/configure.ac
index feb4e50..3105ff3 100644
--- a/builds/unix/configure.ac
+++ b/builds/unix/configure.ac
@@ -1,6 +1,15 @@
# This file is part of the FreeType project.
#
# Process this file with autoconf to produce a configure script.
+#
+# Copyright 2001, 2002, 2003, 2004, 2005 by
+# David Turner, Robert Wilhelm, and Werner Lemberg.
+#
+# This file is part of the FreeType project, and may only be used, modified,
+# and distributed under the terms of the FreeType project license,
+# LICENSE.TXT. By continuing to use, modify, or distribute this file you
+# indicate that you have read the license and understand and accept it
+# fully.
AC_INIT
AC_CONFIG_SRCDIR([ftconfig.in])