Sticky DOF not working

[thany]

I've got a 550D and ML 2.3, and the "Sticky DOF" setting doesn't appear to be working.

The DOF key remains as it is. There's not much more to it I guess.
How to fix?

[1%]

It should only work in 1 mode I think: photo mode...

In movie mode it automatically sets the aperture always.

You should see something on the screen when you press it once that DOF sticky is on.