[Dovecot] mdbox-files over 2 MB

[Hardy Flor]

Hello,

I received an e-mail, this includes 9 forwarding, each with a file. 
These files are not removed from the e-mail and stored in the 
attachments-directory, although they are larger than 16 KB. For all 
files the "Content-Transfer-Encoding: base64" is set.
The email is stored in completely in "m.00000034"

------------------------------------- doveconf:

# 2.2.12: /etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-4-amd64 x86_64 Debian 7.4 ext4
mail_attachment_dir = /var/mail/attachments
mail_attachment_hash = %{md5}
mail_attachment_min_size = 16 k
mail_location = mdbox:/var/mail/user/%n
mdbox_rotate_interval = 1 weeks
mdbox_rotate_size = 2 M

------------------------------------- directory:

root at xxx:/var/mail/user/xxx/storage# ls -al
...
-rw------- 1 vmail mail 14433784 Mär 16 13:51 m.00000034
...