Yes. Sieve uses the same functions for saving mails as the rest of Dovecot. It happened again, so I have more input:
I have several of these: Oct 9 00:41:22 xxx dovecot: deliver(xxxxxx): fdatasync(/import/mail/xxxxxx/dovecot-uidlist) failed: Disc quota exceeded Oct 9 00:41:22 xxx dovecot: deliver(xxxxxx): sieve: msgid=<XXXXX>: stored mail into mailbox 'INBOX'
I also have this one: Oct 6 18:14:47 xxxx dovecot: IMAP(xxxxxx): Broken file /import/mail/xxxxxx/.Trash/dovecot-uidlist line 4: UIDs not ordered (8171 >= 8172) Oct 6 18:14:47 xxxx dovecot: IMAP(xxxxxx): fdatasync(/import/mail/xxxxxx/.Trash/dovecot-uidlist.tmp) failed: Disc quota exceeded Oct 6 18:14:47 xxxx dovecot: IMAP(xxxxxx): Panic: file maildir-save.c: line 653 (maildir_transaction_save_commit_pre_sync): assertion failed: (first_uid != 0) Oct 6 18:14:47 xxxx dovecot: dovecot: child 15337 (imap) killed with signal 6 (core not dumped - set mail_drop_priv_before_exec=yes)
Hope that helps tracking down the bug.