corruption when using sieve vacation message?

[E.H.Eefting]

When using this vacation message:
    require "vacation";
    vacation "phatte test";
    vacation :addresses "test at d.nl" "phatte test";

My cyrus database gets corrupted after it tries to reply to the first received message:
Dec 23 20:28:26 darkstar sieve[23096]: executed
Dec 23 20:28:26 darkstar sieve[23096]: accepted connection
Dec 23 20:28:28 darkstar sieve[23096]: login: dikke.geert.nl[127.0.0.1] test PLAIN User logged in
Dec 23 20:28:31 darkstar sieve[23096]: entered bc_action_emit with filelen: 16
Dec 23 20:28:37 darkstar master[22443]: process 23096 exited, status 0
Dec 23 20:28:49 darkstar master[23163]: about to exec /usr/cyrus/bin/imapd
Dec 23 20:28:49 darkstar imap[23163]: executed
Dec 23 20:28:49 darkstar qmail: 1166902129.468046 new msg 25329441
Dec 23 20:28:49 darkstar qmail: 1166902129.468658 info msg 25329441: bytes 849 from <zend at d.nl> qp 23162 uid 115
Dec 23 20:28:49 darkstar imap[23163]: accepted connection
Dec 23 20:28:49 darkstar qmail: 1166902129.514841 starting delivery 18: msg 25329441 to local d.nl-test at d.nl
Dec 23 20:28:49 darkstar qmail: 1166902129.515399 status: local 1/10 remote 0/20
Dec 23 20:28:49 darkstar imap[23163]: login: dikke.geert.nl [127.0.0.1] zend plaintext User logged in
Dec 23 20:28:49 darkstar qmail: 1166902129.553515 new msg 25329442
Dec 23 20:28:49 darkstar qmail: 1166902129.554240 info msg 25329442: bytes 947 from <zend at d.nl> qp 23165 uid 50
Dec 23 20:28:49 darkstar qmail: 1166902129.580819 starting delivery 19: msg 25329442 to local test at dikke.geert.nl
Dec 23 20:28:49 darkstar qmail: 1166902129.581397 status: local 2/10 remote 0/20
Dec 23 20:28:49 darkstar qmail: 1166902129.581677 delivery 18: success: did_0+1+0/qp_23165/
Dec 23 20:28:49 darkstar qmail: 1166902129.582291 status: local 1/10 remote 0/20
Dec 23 20:28:49 darkstar qmail: 1166902129.582566 end msg 25329441
Dec 23 20:28:49 darkstar imap[23163]: seen_db: user zend opened /home/system/cyrus-imap/user/z/zend.seen
Dec 23 20:28:49 darkstar imap[23163]: open: user zend opened INBOX.Sent
Dec 23 20:28:49 darkstar master[23174]: about to exec /usr/cyrus/bin/lmtpd
Dec 23 20:28:49 darkstar lmtpunix[23174]: executed
Dec 23 20:28:49 darkstar lmtpunix[23174]: accepted connection
Dec 23 20:28:49 darkstar lmtpunix[23174]: lmtp connection preauth'd as postman
Dec 23 20:28:49 darkstar imap[23163]: seen_db: user zend opened /home/system/cyrus-imap/user/z/zend.seen
Dec 23 20:28:49 darkstar imap[23163]: open: user zend opened INBOX.Sent
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_check: ^O^\\224¿|[^M>&>^RsJ^A^_T                         test                 0
Dec 23 20:28:50 darkstar lmtpunix[23174]: mystore: starting txn 2147483654
Dec 23 20:28:50 darkstar lmtpunix[23174]: mystore: committing txn 2147483654
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_mark: ^O^\\224¿|[^M>&>^RsJ^A^_T                         test                 1167506930 0
Dec 23 20:28:50 darkstar lmtpunix[23176]: FATAL: couldn't exec() sendmail
Dec 23 20:28:50 darkstar lmtpunix[23174]: sieve runtime error for test id <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>: Vacation: Sendmail process terminated normally, exit status 75
Dec 23 20:28:50 darkstar lmtpunix[23174]: DBERROR db4: Locker does not exist
Dec 23 20:28:50 darkstar lmtpunix[23174]: DBERROR: error fetching <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>: Invalid argument
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_check: error looking up <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>/user.test: cyrusdb error
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_check: <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl> user.test            0
Dec 23 20:28:50 darkstar lmtpunix[23174]: IOERROR: opening /home/system/cyrus-imap/maildir/stage./23174-1166902130-0: No such file or directory
Dec 23 20:28:50 darkstar lmtpunix[23174]: sieve runtime error for test id <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>: Keep: System I/O error
Dec 23 20:28:50 darkstar lmtpunix[23174]: DBERROR db4: Locker does not exist
Dec 23 20:28:50 darkstar lmtpunix[23174]: DBERROR: error fetching <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>: Invalid argument
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_check: error looking up <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl>/user.test: cyrusdb error
Dec 23 20:28:50 darkstar lmtpunix[23174]: duplicate_check: <6278953.1166902129007.OPEN-XCHANGE.WebMail.nobody at dikke.geert.nl> user.test            0
Dec 23 20:28:50 darkstar lmtpunix[23174]: IOERROR: opening /home/system/cyrus-imap/maildir/stage./23174-1166902130-0: No such file or directory
Dec 23 20:28:50 darkstar lmtpunix[23174]: IOERROR: error unlinking file /home/system/cyrus-imap/maildir/stage./23174-1166902130-0: No such file or directory
Dec 23 20:28:50 darkstar dspam[23172]: Delivery agent returned exit code 75: /usr/cyrus/bin/deliver -a test test
Dec 23 20:28:50 darkstar qmail: 1166902130.152295 delivery 19: deferral:
Dec 23 20:28:50 darkstar qmail: 1166902130.153858 status: local 0/10 remote 0/20

Notice the strange duplicate marks.
Using glibc 2.3.3 and gcc 3.3 on a 2.6.18.8 kernel.
The above output is from a just installed 'clean' system.
I also tried it on another setup, with the same results.
I'm using using cyrus imap 2.2.12.

We've been using cyrus imap on many servers for serveral years without problems, however this is the first time we tried to use Sieve.
Any ideas as to how this corruption might happen? 

Many thanks!
Edwin Eefting
www.syn-3.nl