Hot Spot in Browsers

not working for FireFox, Safari, Chrome

I saw one of the tutorials and I am impressed!
Currently, I try to get one cursor to work for a web project.
Typical browsers that need to be supported are Internet Explorer, FireFox, Safari, Chrome on Windows, the last three also on Mac.
I set the hot spot in my curser to 15, 15. When I use it in Internet Explorer, the hot spot works (similar to crosshair or move). However, in Safari, Chrome or FireFox the hot spot is still in the upper left corner (like nw-resize or pointer.
Is this a know issue?
Thanks,
RSB