Piping through program

Hi,

I have the following problem:

        A mail with a given Subject should be piped
        through a program which produces an output
        on stdout. This output should be sent to the
        originator of the mail, the mail should be
        appended to folder xyz.

Anybody who can help me?

Dirk
-- 
GM of United 2+3 (Fussball-Manager-PBeM).
GM of GC 00x     (Space Opera)

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