[Dovecot] Sieve & Regex

Hi all I'm trying to create a new sieve rule.

What I would like to do is catch "From" addresses that are equal to the rightpart (hostname) of a message-id.

For example:

Message-ID: 000d01c9d23a$941a7db0$6400a8c0@upwabm From: "Leanne Crabtree" upwabm@blomberg-co.com

I would like to catch this mail, because it has "upwabm" on the right part of the message-id and "upwabm" on the left part of the sender address.

I've done this, but with no success. The error reported is: "Invalid preceding regular expression" on line with the second regex with ${1}

More over I would like to add an header with the result of regex, an header like this:

"X-MyHeader" "${1}" but it does not work.

This is an extract of our sieve:

require ["regex"]; if header :regex "Message-ID" "^.*@(.*)>$" { if header :regex "From" ".*<${1}@.*>$" { addheader "X-MyHeader" "${1}" } }