lockCursor not working since update

ever since i updated unity lockCursor has stopped working, showCursor still works but lock doesn't.

I am experiencing a similar problem. My working G2G Tutorial (Gamer To Game Developer - Unity 3 & 4 Tutorials) was working fine until I upgraded to 4.0. Now it seemes there are issues with Screen.lockCursor not functioning when I access the menu system.

After further testing I now realize that lockCursor is working fine. My understanding of lockCursor was incorrect.

To clarify my mistaken problem in case it helps others…
I had changed some imported scripts like the FPS Controller, Mouse Look and such. When I upgraded, these were re-imported overwriting my changes. Once I added my changes back to the imported scripts everything worked as expected.