Host:Service recovered Mail with attachment

Hi all,

I migrated last week from version 4.0.2 (32bit) to 4.3.7 (64bit).
Everything was very easy and smooth.
But one thing leaves me puzzled. While the 'host:service critical' mails I receive are in plain text, the 'host:service recovered' mails have no text, but an attachment called 'Mail-Attachment' which contains the message.

Thx in advance for any hint
Daniel
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