Inexplicable material of my object...

Hi everybody…

I think the sollution for problem is a simple sentence but I dont know it.
I have created a simpe object with subsurf and It has tuned out.
What can I do against it?
http://http://beprog.extra.hu/monitor.jpg
http://beprog.extra.hu/monitor.jpg
http://beprog.extra.hu/monitor.jpg

The link is dead for me.