dovecot - Nov 2010 - alternate sendmail binary for sieve redirect OT

Hi , this isnt really a dovecot/postfix question
in dove lda, there is sendmail_path someone tried other progs here like
mini_sendmail ?

http://www.acme.com/software/mini_sendmail/

i.e for using a default from forwarder address when sending redirects by
sieve....is a stupid idea?

background, some other mail providers use a default sender forwarder
mailaddress when redirect
this may avoid problems at forwarding with spf etc

any other idea to reach this goal, pipe etc?
-- 
Best Regards

MfG Robert Schetterer

Germany/Munich/Bavaria