New UI in V4.6 - rendering error using masks in deferred rendering.

For my project I’m using Unity 4.6 new UI system.
I’m drawing my canvas in World Space mode and seem to be having a depth buffer render problem.

So this is the setup I have:
Just a Canvas with a UI.Image object that has a nested UI.Text (this is the image object)

And if there is ANY geometry behind the text then it wont render it:

This only seems to happen in deferred rendering. If I switch to forward rendering then the text shows up correctly.
Is this the normal behaviour? Am I doing something wrong? Are there any workarounds?

If someone is still interested in solving this issue: UnityIssueTracker-MaskingUIWorldSpace

The problem with mask and deffered rendering should be fixed in Unity 5.2, but for all lower versions you can clear the stencil buffer of the camera: Camera.clearStencilAfterLightingPass