Hello,
I've installed Silverstripe 2.3.3 and the newsletter module trunk-r91174 (newsletter-trunk-r91174.tar.gz). I've followed these docs (http://doc.silverstripe.org/doku.php?id=modules:newsletter and http://doc.silverstripe.org/doku.php?id=newslettersytemhelp).
But, when i want to add a new recipient, i have the green message that say "New member added" but nothing in my database, and nothing in the list in admin panel : no new member... No error...