We developed a newsletter mailserver. We send mail with special caharacters UTF-8 and base64 encoded. This works for all mail clients except Groupwise. In the Groupwise e-mail client the subject is displayed base64 encoded.
I attached the e-mail header at the end of this message.
My question is: Why is the subject displayed in base 64 encoding en how can we fix this?
Thank you very much for any help on this issue!
Best regards,
Ben van der Linden

Microsoft Mail Internet Headers Version 2.0
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Date: Tue, 15 Feb 2011 14:44:21 +0100
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Subject: =?UTF8?B?Rm9Cb1M6IEZvciBzYWZlciBmb29k?=
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Content-Type: text/plain; charset=utf-8
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