antispam plugin pipe backend error when moving multiple emails

[Stéphane Cottin]

Hi,

I've got some trouble with the dovecot antispam plugin and the pipe backend.

I'm using dovecot 2.2.18 with maildirs and zlib compression enabled.

When moving 2 or more emails at once from the Junk folder to another one, I always have the following error : "Failed to copy to temporary file"

In the server logs : 

imap(vvv at vvv.vvv): Error: read(zlib(/data/Maildir/.test/tmp/1446974366.M123890P936.vvv)) failed: Cached message size smaller than expected (13553 < 13562, box=test, UID=0)

The same operation with one email at a time, on the same emails, works as expected.

Stéphane