.option dkim_private_key smtp string&!! unset
.option dkim_canon smtp string&!! unset
.option dkim_strict smtp string&!! unset
-.option dkim_sign_headers smtp string&!! unset
+.option dkim_sign_headers smtp string&!! per RFC
.option dkim_hash smtp string&!! sha256
.option dkim_identity smtp string&!! unset
DKIM signing options. For details see section &<<SECDKIMSIGN>>&.
unsigned. You can use the &%$dkim_domain%& and &%$dkim_selector%& expansion
variables here.
-.option dkim_sign_headers smtp string&!! unset
-If set, this option must expand to (or be specified as) a colon-separated
+.option dkim_sign_headers smtp string&!! see below
+If set, this option must expand to a colon-separated
list of header names. Headers with these names will be included in the message
signature.
When unspecified, the header names recommended in RFC4871 will be used.
+The default list is available for the expansion in the macro
+"_DKIM_SIGN_HEADERS".
.section "Verifying DKIM signatures in incoming mail" "SECID514"