shader/layer overlapping problem

Hello Unity Answers Community.

I've got the following problem: My current Project is a 2D side scrolling game that uses the parallax effect with some Planes as Layers in the Background. The Problem is that they are overlapping at some times whats an very odd behaviour. I just have no clue how to fix this.

Ive attached also some screens so it might be clearer whats my problem. I tried also different spaces between the planes in the background without any success.

http://s7.directupload.net/file/d/2407/xpq8pz43_jpg.htm

http://s13.directupload.net/file/d/2407/exnrfqqw_jpg.htm

http://s3.directupload.net/file/d/2407/raju7ylu_jpg.htm

http://s3.directupload.net/file/d/2407/mhh6u9g9_jpg.htm

It's easy to fix this, because they're flat an in the same plane. Put the ones you want in front in a later queue. You don't need need to worry about positioning them in the Z axis (as long as your shader uses ZWrite Off, which is typical).

http://unity3d.com/support/documentation/ScriptReference/Material-renderQueue.html

There really is no thing as transparency. Instead, meshes just blend their colors into what's already been rendered. So, you have to ensure that the rendering occurs in the proper order, or weird-looking things happens. I talk about the problem near the end of this video.