remailer help -

I am writing, for lack of a better term, a mail server.
The user sends email from my web page to this mail
server.  Initially, I test for "Contact site Admin"
that's in the body of the initial email and then 
send the email out to one of my clients.  Note that
I insert the email of the initiator into a header
field named "X-Mailto-Comment:" not with procmail 
but in the perl mailer fired off from the web page.
I also write the subject of the email into a file.
This code seems to work fine.

:0 Bc
      * Contact site Admin
      | formail -cz -I "From: purple(_at_)visi(_dot_)com" \
      | $SENDMAIL -oi $ADMIN

      :0 wci:
      * ^Subject:[    ]\/[^   ].*
      | echo "Subject is: " $MATCH  >>$HOME/BHmail_log
   
question:  what's the difference between formail -rt 
and formail -cz?  I can't seem to find a list of
formail options.

Because I inserted the "From: purple(_at_)visi(_dot_)com", the 
client can now just reply to the message and it goes
back to the mail server.  The client's email header
indeed contains the line

"X-Mailto-Comment: originator(_at_)email(_dot_)address"

I am trying to have the mail server extract "client(_at_)email(_dot_)address"
from the "X-Mailto-Comment:" field and put it into the TO
field and put the clients email address in the "From:" 
I am failing badly at this.  Any help would be appreciated.
No match appears for the "X-Mailto-Comment:" line
Tom

#test to see if a reply from client
:0
* ^Subject:.*Re: HawkWeb    
 {
    :0c 
     * ^X-Mailto-Comment:[    ]\/[^   ].*
      | echo "X-Mailto-Comment: " $MATCH >>$HOME/BHmail_log  
      initiatoremail = $MATCH
    
    :0c 
      * ^Subject:[    ]\/[^   ].*
      | echo "Subject is: " $MATCH  >>$HOME/BHmail_log
       
      
     :0
      | formail -cz  \
      | $SENDMAIL -oi $initiatoremail
}

I think the "FROM:" will show up as that of the client who
is replying, but I can't get that far.