I use WP 3.4.2 and your plugin versioned 2.3.9.
When I try to register a new user I receive the email with activation link but when I click it I don't receive any confirmation email with the password generated.
I don't think it's an SMTP issue, because I always get the first email message with activation link.
I've tried with a couple of different email address domain...I don't know if it could be a "false spam" issue (something inside headers or object) or something else...
I think it could be some issue related to cimy_uef_email_handler.php about at line 64...but I'm not sure and I can't find a solution by myself.
Could you please help me ?!? Thank you in advance!