Check the HTTPS/SSL-settings in Joomla and on the server (if possible) - you can also check the SSL-settings in different browsers to see if it makes any difference...
It wouldn't surprise me if it's a "Joomla screw-up"
Please reply with a direct link to the issue & create a new thread for each new issue.
A template is only as good as the content that goes into it - DanG
Found a quick work around for the time being - changed the Encrypt Login Form to NO. This at least lets users log in and out.
BTW - I have checked other browsers - same issue on all of them. Encrypted Login Form does not work I will have a look again with a "fresh eye" today, maybe I'll spot something.