Ok, thanks, that would be an alternative.
But I achieved it already with the js function. And as I want to work for longer time with these data it would be much more comfortable to edit them by php/mysql.
As I mentioned before, by using js within a Hotspot style, I could get access to the variable "name". But - as I am not really through this xml stuff - it did not work with a self determined variable like" owner" which I defined within the Hotspot tag. If I cannot define variables by myself, are there any other given variables which I can use in the Hotspot tag? Or is there a way to define new variables to use?