Ok, my provider did fix the fault and now everything is back again, also the testing site. :-)
The main mobiki site is actually up and running again. All my domains do run well if configured for Apache/PHP5.3, but do actually not run with the providers setup for PHP 5.4 as FastCGI server. So...
I'm sorry, but since tonight all my 8 domains and the correspondending webservers at my provider are down. Hope, they will fix it soon.
A very cool software. I use it for calendar and contact sync with my Android phone hosted at my provider and at home for sharing my dokuments and media files.
For now there are two example websites using mobiki: my own website http://döring.net/index.php in german language and the mobiki.datenbrei.de site itself.