[exim] permanent error if delivery ends with segv

Hello,

From time to time, the procmail delivery transports fails because
procmail terminates with a sigsegv. Our problem is that this generates
a permanent error, and the original mail is lost.

How can we change such errors as temporary ones ?

Some details:

- Exim 4.52, running on Debian sarge

- router:

procmail:
    driver = accept
    check_local_user
    transport = procmail_pipe
    require_files =
    ${local_part}:+${home}:+${home}/.procmailrc:+/usr/bin/procmail

- transport:

procmail_pipe:
debug_print = "T: procmail_pipe for $local_part@$domain"
driver = pipe
path = "/bin:/usr/bin:/usr/local/bin"
command = "/usr/bin/procmail"
return_path_add
timeout = 0s
transport_filter = /usr/bin/tr -d \\000
# delivery_date_add
# envelope_to_add



- sample error:

2006-03-21 21:13:24 1FLnEG-0005Xj-Vk ** <user>@mail-veri.imag.fr
R=procmail T=procmail_pipe: Child process of procmail_pipe transport
(running command "/usr/bin/procmail") was terminated by signal 11 (Segmentation fault)


Thanks,
--
Nicolas