I've been wondering the same thing.  I run rexxc on every program prior to going into production and following any change (no matter how minor) and I have to see this everytime. 
Open Object Rexx Tokenizer Version 3.0.0
Build date: Mar 28 2005
Copyright (c) IBM Corporation 1995, 2004.
Copyright (c) RexxLA 2005.
All Rights Reserved.
This program and the accompanying materials
are made available under the terms of the Common Public License v1.0
which accompanies this distribution.
-----Original Message-----
From: oorexx-devel-admin@lists.sourceforge.net [mailto:oorexx-devel-admin@lists.sourceforge.net] On Behalf Of Rony G. Flatscher
Sent: Friday, November 11, 2005 9:12 AM
To: oorexx-devel@lists.sourceforge.net
Subject: [Oorexx-devel] A question on license referrals...

Hi there,

just curious: would it be sufficient to include in (Rexx) programs the following line to make it clear the license that applies to it?
license:          CPL 1.0 (Common Public License v1.0, see accompanying file "CPLv1.0.txt")
This way one could fogo that boring copy-block at the beginning of the programs.