[Exim] Amavis eating up bounces

Hello,

I installed Amavis and it is working, but bounces are simply
vanishing:

2001-06-30 12:00:23 15GHY7-0008JW-00 <= marc@??? U=uucp P=local-bsmtp S=635
id=20010630120011.A969@???
2001-06-30 12:00:23 15GHY7-0008JW-00 ** lsdkjfsdf@???: unrouteable mail domain
"sdfsdfsdf.de"
2001-06-30 12:00:23 15GHY7-0008JY-00 <= <> R=15GHY7-0008JW-00 U=root P=local S=1461
2001-06-30 12:00:23 15GHY7-0008JW-00 Error message sent to marc@???
2001-06-30 12:00:23 15GHY7-0008JW-00 Completed
2001-06-30 12:00:27 15GHY7-0008JY-00 => marc <marc@???> D=amavis_director T=amavis

Jun 30 12:17:25 gandalf amavis[32190]: starting. amavis perl-11 Fri Jun 29 19:26:08 CEST 2001
Jun 30 12:17:26 gandalf amavis[32190]: do_exit:374 - ending execution with 256

So Amavis cannot deliver the bounce, I think, but I don't know why.
How can I get more information about what is going wrong?

exim.conf:

trusted_users = uucp:mail:root:marc:www:amavis

amavis:
driver = pipe
command = "/usr/sbin/amavis -f ${sender_address} -d ${pipe_addresses}"
prefix =
suffix =
check_string =
escape_string =
# for debugging change return_output to true
return_output = true
return_path_add = false
user = amavis
group = mail
path = "/bin:/sbin:/usr/bin:/usr/sbin"
current_directory = "/var/amavis"

amavis_director:
condition = "${if eq {$received_protocol}{scanned-ok} {0}{1}}"
driver = smartuser
transport = amavis

Thanks,
Marc