Upgrade worked very seamlessly. Thanks to Varien Team!
One issue arised from one installation: it was originally installed in a directory /var/www/html and “html” was renamed to /var/www/golfdiscount.de. Now the upgrade tried to access /var/www/html. The workaround “ln -s /var/www/golfdiscount.de /var/www/html” worked fine and upgrade to 1.1.7 worked perfect then. After upgrade the symbolic link “html” was removed.
Maybe someone can tell me where in the guts of Magento this reference lies
Other upgrades on other shops worked just like a breeze. (did 3 upgrades in total until now)