In message <20040222144104.GM11328@phaeton.entropie.net>, Martin Weber writes:
>This is, as I said, the 2nd point (to which you replied), where reverse 
>dns DOES resolve, but to another IP than where the mail is coming from. 
>If you check that the mail's path also maps to where it claims to be 
>coming from, you'll be stumbling over that. It's no difference whether I
>claim to be (global) entropie.net but am it only locally, or whether I
>claim to be the toplevel domain, and am not.  Thus i'm still out.

I don't think I understand.  Where does anyone ever have to see
"entropie.net"?  Your ISP gives you an address which resolves to
<mumble>.example.com; you set sendmail to HELO as example.com.
No other name seems relevant to this; we're talking about envelope senders,
not what might or might not be in your From line.

-s