Can't save blocks in all 6.x. versions

Hi all,

I'm having a strange problem, i recently moved my website to a new server and now i'm having difficulties with the homebox module. When i want to add or change blocks in the Layout of my homebox, i can't save them. The blocks are set back as they were.

I have tried several versions of the homebox 6.x., but none worked. I have tested changing my blocks in FF, Chrome & IE. I thought that it could be a Jquery or Ajax problem, so i disabled my Ajax modules, but these weren't the problem.

My settings:
jQuery UI 1.6
jQuery Update 1.3.2
PHP 5.3.18

It's very strange because on my localhost the Homebox module does work (i can save blocks). Can it be a server config?

For more info, just ask.

Thanks in advance!
Gunther