[EXIM] Address rewrite

I'm using the "SMTP after POP service" of GMX (SMTP-relaying is restricted
to GMX-users which are logged-in or just using the POP-connection via
fetchmail)
Therefore I need to rewrite the env-from header of outgoing mail
before the SMTP dialog to GMX begins.

I do this through a rewriting rule in the configure-file. But now _all_
mail is rewritten not only outgoing mail.

1) Can I restrict address rewriting to outgoing mail?

2) Is it possible to rewrite through headers_remove / headers_add the
env-from header? If yes: Does this work before the SMTP dialog to GMX
begins?

Thanks in advance.
Rudolf

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Rudolf Kompf                     | EMail: Rudolf.Kompf@???

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