deliver in 2.3.1 cause Memory fault

[Patrice]

Hi,

I used this command on 2.2.12 to make a local delivery for warning messages.

cat mymail.txt|deliver  -- toto at mydomain.com


with mymail.txt being correctly formatted.
the deliver was working fine.

the same command with 2.3.1 cause a Memory fault
with no log.

I tried to use the deliver binary from 2.2.12 on my new 2.3.1 tree it 
works (mail delivered)
but this appears in my log file:
IOERROR: locking header for user.toto: Resource deadlock avoided
and imap does not respond anymore till a restart.

I searched for the same problem but I haven't found any clue.
thank you for your help.

Best Regards
Patrice