Flickering mesh graphics.

When using a camera and meshes it seems like there are some graphics glitches when the items are on the border of the screen. Here is an example with some ellipses that start to flicker when they are half outside of the screen. Any idea why? (can I disable the depth check?)

http://m.youtube.com/#/watch?feature=youtube_gdata_player&v=iHt57DeWCrU&desktop_uri=%2Fwatch%3Fv%3DiHt57DeWCrU%26feature%3Dyoutube_gdata_player&gl=SE