Multiple "Content-transfer-encoding:" fields in email header

Hi,
I'm running now nmh-0.27 with exmh 2.0.2 on my Unix system but since the
sendmail.8.9.1a patch
installation, multiple "Content-transfer-encoding:" fields are sometimes
inserted in email headers.
For example, a forward command excuted in old-style (not MIME) under
exmh through forw nmh command (without -mime flag) gives the following
results :

With sendmail.8.9.1 :

Delivery-date: Wed Aug 19 11:55:15 1998
Received: from vega.idris.fr (saive(_at_)localhost)
 by vega.idris.fr (8.9.1/8.9.1) with ESMTP id LAA97040
 for <saive>; Wed, 19 Aug 1998 11:55:15 +0200
Message-id: <199808190955(_dot_)LAA97040(_at_)vega(_dot_)idris(_dot_)fr>
X-mailer: exmh version 2.0.2 2/24/98
Mime-version: 1.0
Content-type: text/plain; charset=iso-8859-1
Content-transfer-encoding: 8bit
To: saive
Subject: forw old-style exmh 2.0.2 sendmail 8.9.1
Date: Wed, 19 Aug 1998 11:55:14 +0200
From: Claude Saive <saive>
...

With sendmail.8.9.1a :

Delivery-date: Wed Aug 19 11:58:54 1998
Received: from vega.idris.fr (saive(_at_)localhost)
 by vega.idris.fr (8.9.1a/8.9.1) with ESMTP id LAA60502
 for <saive>; Wed, 19 Aug 1998 11:58:54 +0200
Message-id: <199808190958(_dot_)LAA60502(_at_)vega(_dot_)idris(_dot_)fr>
X-mailer: exmh version 2.0.2 2/24/98
Mime-version: 1.0
Content-type: text/plain; charset=iso-8859-1
Content-transfer-encoding: 8bit
Content-transfer-encoding: 8bit
To: saive
Subject: forw old-style exmh 2.0.2 sendmail 8.9.1a
Date: Wed, 19 Aug 1998 11:58:54 +0200
From: Claude Saive <saive>
...

And then, in line mode with show command (nmh package), the following
messages are obtained :

mhn: message xxx has multiple Content-Transfer-Encoding: fields (8bit)
mhn: unable to decode xxx

Did you already get this problem and how to solve it ?
Thanks for your help
Regards

Claude

--
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    Saive Claude                               Groupe Reseau/Network Team
    CNRS/IDRIS                              Tel:        +33 1 69 35 84 20
    BP 167                                  Fax:        +33 1 69 85 37 75
    91403 Orsay Cedex, France               E-Mail: 
Claude(_dot_)Saive(_at_)idris(_dot_)fr
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