Version: (using KDE 4.3.0) OS: Linux Installed from: Ubuntu Packages With my CAcert certificate for my IMAP server I'm suffering of the infamous bug 162485 on startup. If the warning dialog isn't discarded quick enough, it seems like KMail silenntly loses the connection to the IMAP server (dovecot in my case). This results in a stale inbox (ie. I see the mails from the last time I had KMail open) but isn't noticeable until you try to refresh that folder or switch folders (which runs into a timeout).
Thank you for taking the time to file a bug report. KMail2 was released in 2011, and the entire code base went through significant changes. We are currently in the process of porting to Qt5 and KF5. It is unlikely that these bugs are still valid in KMail2. We welcome you to try out KMail 2 with the KDE 4.14 release and give your feedback.