For historical reference only - Due to the problems described below, Passpack no longer uses this IMAP method of authentication. Read more here.
When you login via the Gmail third party login, Passpack uses IMAP to ping your account and authenticate you. No email is read, just a ping to authenticate you.
This may sometimes cause Google to alert you of suspicious log-in activity is detected on your account, for example, "Warning: We believe your account was last accessed from..." followed one of the following Passpack IP addresses
(all three are in Germany)
To check the activity on your account (even when there is no alert) you can click the "Details" link next to the "Last account activity" line at the bottom of any Gmail page shows information about recent activity in your mail. For each time you login to Passpack via the thirdparty association, you should see 1 connection via IMAP. If everything looks ok to you, click dismiss to let Google know the log-in activity was legitimate.