     Copyright (c) Massachusetts Institute of Technology 1994, 1995, 1996.
     All Rights Reserved.
     Unpublished rights reserved under the copyright laws of
     the United States.

 THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
 OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.

 This code is distributed freely and may be used freely under the 
 following conditions:

     1. This notice may not be removed or altered.

     2. This code may not be re-distributed or modified
        without permission from MIT (contact 
        lclint-request@larch.lcs.mit.edu.)  

        Modification and re-distribution are encouraged,
        but we want to keep track of changes and
        distribution sites.

