Exim4 & RT3.4 issues

Dear All,

As a new member of the rt family, I have some questions related to the
installation of RT3.4 in a Debian box. As you already know Debian prefers
exim. I have to admit that I do not have much experience with this MTA,
though I decided to keep exim instead of replacing it with sendmail or
qmail.
I have also went through the existing Wiki and most of the archives of this
list but unfortunately I have not a clear picture on how the MTA should act.
Therefore, I would like your comments.

In the /etc/aliases file I did not add anything since exim4 doe’s not allow
addresses piping to other programs.
In the /etc/exim4/conf.d/router:
rt:
debug_print = "rt for $local_part@$domain \n local_part: $local_part \n
local_part_suffix: $local_part_suffix"
driver = accept
transport = rt_pipe
domains = “rt.seeren.org
#local_parts = "^rt(-.)?"
local_part_prefix = "rt-"
local_part_suffix = “-action:-comment:-correspond”
#local_part_suffix = +

#local_part_prefix = *-
#new_address = ${quote:${lc:${local_part}}}@${domain}
local_part_suffix_optional

In the /etc/exim4/conf.d/transport:
rt_pipe:
driver = pipe
command = “RTPATH/rt-mailgate
–action ${quote:${substr_1:$local_part_suffix}}
–queue ${quote:$local_part}
–url http://rt.seeren.org/
#new_address = ${quote:${lc:${local_part}}}@${domain}
#return_path_add
return_output
log_output
#local_part_prefix = “”
#local_part_suffix = ""
user = www-data

To create a new ticket I have to send an email to:
rt--action@<domain_name>
Sending to rt@<domain_name> or to rt-@<domain_name> always fails.
Is this normal behaviour?
When I receive the auto-reply message, the Reply-To field points to
rt@<domain_name>. Should this be corrected from the exim config files or
from the queues configuration via the web interface?

Regards and sorry for the long-winded mail

Yannis