Yes, I know that. Manually with FTP upgrade works. Upgrading Joomla and components in backside is very nice feature. When I install clear Joomla 2.5.4 and after that template sportal25 all works correctly. In that case you can as admin in backside upgrade Joomla to new versions. But that is not possible if template installed with hot_sportal25_hotstart.zip.
I sent information only as remark for situation with hotstart package.
Regards.
Automatic update sometimes doesn't work if you did not properly set TMP folder, or some folders are not writable, or path is your configuration.php is not correct.