Combining actions with templates?

I have some automation that seems like it should be do-able with actions
and templates, but I can't figure out how it should work.  I'm still an
almost complete novice at Sylpheed, so please bear with me.  Here's the
situation:

I moderate some restricted membership lists on Yahoo!  When I get an
email informing me that someone wants to join, the subject line of that
message contains the email address of that person.  I want to run a perl
script to parse the subject line to get the email address, and then
automatically put that in the 'To:' field of an outgoing message which
uses a template.  So in a sense, I want the 'To:' field of the template
to be filled in with the output of an action.

That way, when someone wants to join, I can easily send a "who are you
and what do you want?" message before approving the membership.

Ideas?

Thanks very much,

-pd


-- 
--------
                             Peter Davis
               Funny stuff at http://www.pfdstudio.com
                 The artwork formerly shown as prints
    List of resources for children's writers and illustrators at:
                  http://www.pfdstudio.com/cwrl.html


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