Hi qys,
usually you don't do that. Firstly because mailing lists don't work like forums, where the original thread gets bumped to the top, but instead the original thread stays there and only a new message is added, not the thread bumped. Additionally, they don't list it in their Netiquette, but I'm pretty sure they won't appreciate it having an unnecessary junk message added just to draw attention to a mail, that probably everyone got in first place.
