[Exim] cyrus deliver and exim

This is not entirely an exim matter but I am sure someone will know
enough to point me in the right direction.

The problem I have is with the SIEVE 'vacation' command. This comes
with cyrus 1.6.24. The idea is that the user has a SIEVE (mail
filtering) script installed on the mail server. IMAP looks at this and
deals with mail accordingly. In the case of the vacation command an
auto-response is sent to the sender of the message explaining that the
recipient is on holiday, or whatever.

This version of deliver has the path to sendmail coded in
(/usr/lib/sendmail). The autoresponder does work with standard
sendmail. However, if I replace /usr/lib/sendmail with a link to
/opt/exim/bin/exim a message is sent but all the headers are left blank
and form part of the message. ie the BODY of the message looks like
this.

------------------------------------------
Date: Fri, 19 Jan 2001 15:25:03 +0000
X-Sieve: cmu-sieve 2.0
From: <bucsuser@???>
To: <ccsphc@???>
Subject: Re: vacation test 2
Auto-Submitted: auto-generated (vacation)
Sender: Mail Server <cyrus@???>


test vacation message
-------------------------------------------


Does this ring any bells?

-------------------
P Christie
ccsphc@???