Settings values not showing up.

We are experiencing a strange issue with our CiviCRM (4.7.3) installation on Joomla (3.4.8) with MySQLi 5.6.28-76.1-log and PHP 5.6.18.

If I change some of the settings in one of the administration pages, they are correctly updated on the database, but if I get back to that page I don't see the setting anymore. It seems like values for the settings pages are not retrieved correctly from the database.

Steps to reproduce in the attached doc.

At the beginning looked like a cache problem, but we've tried to clean the followings to not avail:

• browser cache (tried different browsers as well)
• joomla cache
• siteground supercacher

We then tried a complete clean installation but the problem is still the same.

It appears to be a bug altough your demo site does not provide a 4.7.3 on Joomla to test.