mx_check {
	enabled = true;
	timeout = 1.0;
	symbol_bad_mx = "MX_INVALID";
	symbol_no_mx = "MX_MISSING";
	symbol_good_mx = "MX_GOOD";
	expire = 86400;
	expire_novalid = 7200;
	greylist_invalid = true;
	key_prefix = "rmx";
}