A quick search of the mail archive turned up this message: http://lists.xymon.com/pipermail/xymon/2011-September/032499.html
It's your mail agent ("Heirloom mailx 12.4", according to your log) that inserts the "Content-type: application/octet-stream" header, that causes your mail reading program to treat the message as an attachment.
Fixing it is outside Xymon.
Regards, Henrik
On Mon, 30 Apr 2012 13:28:20 +0200, Daniel Wolf <daniel at wolfimnetz.de> wrote:
Hi Henrik,
yes, the source of the mails is different. The 'good' or plain text mails have: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit
and the 'bad' ones have: Content-Type: application/octet-stream Content-Transfer-Encoding: base64
but this happens on the xymon server. I see from /var/log/maillog
Apr 30 13:07:40 xymon64 sSMTP[16315]: 354 Start mail input; end with <CRLF>.<CRLF> Apr 30 13:07:40 xymon64 sSMTP[16315]: Received: by xymon64.domain.com (sSMTP sendmail emulation); Mon, 30 Apr 2012 13:07:40 +0200 Apr 30 13:07:40 xymon64 sSMTP[16315]: From: "xymon Monitor" <xymon at xymon64.domain.com> Apr 30 13:07:40 xymon64 sSMTP[16315]: Date: Mon, 30 Apr 2012 13:07:40 +0200 Apr 30 13:07:40 xymon64 sSMTP[16315]: To: daniel at domain.com Apr 30 13:07:40 xymon64 sSMTP[16315]: Subject: Xymon server.domain.com:http recovered Apr 30 13:07:40 xymon64 sSMTP[16315]: User-Agent: Heirloom mailx 12.4 7/29/08 Apr 30 13:07:40 xymon64 sSMTP[16315]: MIME-Version: 1.0 Apr 30 13:07:40 xymon64 sSMTP[16315]: Content-Type: application/octet-stream Apr 30 13:07:40 xymon64 sSMTP[16315]: Content-Transfer-Encoding: base64
KR Daniel
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