This is not gimbal lock, I am not rotating around more than 1 axis.  And this happens to some objects and not others.  Everyone please launch Poser and try this and see what you get, because this scene is about as simple as you can get.

Create a blank scene, add Poser's built-in High-res Ball to the scene.  Add a simple 2D texture map to the ball, with a surface that will make it evident which way the ball is rotating, i.e. don't make it a simple color surface.  In my case I used a earth continent/ocean map.

After you add the surface select the ball and spin the yRotate dial.  What happens?  In my case it does the same thing as spinning the zRotate dial, I can't get it to rotate around the y-axis like a globe should.

Let me know what you get.