Wondering how this came about. I've got a 2.5 SolarSentinel template that is fairly new...about a month. Everything is updated.
However it seems that I"m needing logging in twice.
Usually, if you, for example, registered your domain with www.your_domain.com and you access your domain (admin area) with your_domain.com, you will be forced to double authenticate
The same applies to your_domain.com and www.your_domain.com/administrator
Please try to find the answer to this on the official Joomla forum because this is Joomla related issue and not the template related issue