/* XXX: After scanning through the entire list looking for parents
* via "In-Reply-To", we should do a second pass that looks at the
* list of messages IDs in the "References" header instead. (And
/* XXX: After scanning through the entire list looking for parents
* via "In-Reply-To", we should do a second pass that looks at the
* list of messages IDs in the "References" header instead. (And