AA doesn't work with deferred rendering

When selecting the deferred rendering technical preview option and disabling upscaling but leaving AA on 1-16x the image remains aliased nonmatter the AA value.

What I expected to happen was...:
The edges of lines on screen to appear blurred and the level of blur to change with the values of AA

What actually happened was...:
The image remains aliased nonmatter the AA value.

Steps to reproduce:
1)Select the deffered rendereing technical preview option
2)Disable upscaling
3)Change the AA value