Shadows flickering and grainy pic attached ...help!

[pipesfranco]

I am trying to light my scene I have activated shadows on a deffered light and I am getting a strange cross hatch effect on the shadow and I cant seem to get rid of it.

see image

http://s14.postimage.org/5jy0cpxt9/dots.jpg (http://postimage.org/image/5jy0cpxt9/)

any help is appreciated :)