World editor selection problem?

Okay so In the prospective view, I’m having an issue selecting multiple mesh when using Alt Ctrl and than drag out a selection marquees to group select a cluster of cubes.

When selecting the cubes from the front I get this which looks normal.

However if we take the camera around back of the selected cubes. We see that cubes hiding behind the frontal cubes were not selected at all.
What’s going on here, and how can I select them all in one go?

So is this a bug ? or is it a feature , and if so is there a way to go back to the way UDK handles selections?