Not sending confirmation email

I use the 6.x-2.5 and with this settings the email confirmation is not sent.
I understand that Opt-in (single - not Double Opt-in) not send mail confirmation to subscriber (and also to admin list in mailchimp).
???

possibly related: #1246134: Editing list doesn't set correct setting for double in..

I'm using the latest version of MailChimp and Drupal, and it's not sending email confirmations to me either....

EDIT: just found another issue that addresses the issue as I described it below, here: http://drupal.org/node/1198938

I'm not sure which confirmation email the original poster (@tracyt10) was referring to, but I can confirm there is no email being sent from the Mailchimp STS configuration screen when attempting to verify the "Email from address".

Steps to reproduce:

1. Go to the Mailchimp STS screen, and view "Email options".
2. The first time you visit this screen there is no email address to choose. So under "Verify a new email address" enter a valid email address, and click "Add email".
3. The form reloads and you see a success message "The address info@yourdomain.com has been verified. Please check your email for a confirmation message." You think, "Oh great! I'll go and check my email now". But no email ever comes.
4. Go back to the Mailchimp STS screen, and notice there is also a warning message: "You need to add at least one verified email address to use MailChimp STS."
5. Check "Email options" again, notice that there is still no email address to select from the drop-down menu.
6. Repeat above steps 2-3 more times before giving up and checking the issues cue for the project.

Anyone else having luck getting this to work? I'm running Drupal 7.7 w/ Mailchimp 7.x-2.0

Duplicate of #1198938: MailChimp STS sometimes not sending confirmation e-mails when adding Verified E-mail.