@ Felixsg: That is what I was doing at first, but then I realized that would only work if I was planning to not have anything more than just the ball (an empty planet) in my game forever.
When I start placing people, vegetation, animals, etc... well then each time I take one one step in any direction I would have to start rotating tons of stuff, that would be crazy for the processor, it really is better to just calculate one model's rotation than hundreds of modle's rotations. Besides, if I were to find a way to correclty rotate hundreds of them then i would be able to do just one correctly also (and easier)
Nice idea though! I started with that idea also!

@ MMike: If I get it to work correctly... Yes, it will work perfectly for your work. Feel free to copy the code and play around with it. But i'm kind of stuck now, hope I get some help to finish those problems im having.

@ KiwiBoy: If you use the world coordinates its much more complicated than just modifying z. If you are thinking of z relative to the player model (model's axis) then that is exactly what im doing. But for that to work the player's rotation must be calculated correctly so his z axis is always pointing to the center of the planet (actualy i rotate him so his z axis is towards the center, then I trace towards the core to get the distance to the surface of the planet so he can actually even cimb mountains ans stuff). Currently it is working perfectly for walking forwards/back and strafing side to side, the problem is when I want the player to turn to his left/right (for some reason he likes to face the north pole, and if I try to make him turn away from that either nothing happens, or strange crazy rotations occur).

Please someone help me