Debug results are in:

05.24 08:29 /var/spool/imap/e/user/eler/10. => /home/vmail/eler/cur/10
+.ads-db20
dmz-webmail: channel 9530: new [client-session]
dmz-webmail: Requesting channel_open for channel 9530.
dmz-webmail: Entering interactive session.
dmz-webmail: Sending command: cat "/var/spool/imap/e/user/eler/10."
dmz-webmail: Requesting service exec on channel 9530.
dmz-webmail: channel 9530: open confirm rwindow 0 rmax 32768
dmz-webmail: channel 9530: window 0 sent adjust 32768
dmz-webmail: channel 9530: window 0 sent adjust 32768
dmz-webmail: channel 9530: window 0 sent adjust 32768
dmz-webmail: Warning: ignore packet type 20
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