animation-fill-mode ! not supported ?

Hello there ,

While i was doing some css animation i got these problem in the animation property "animation-fill-mode"  .. And he shows me these : property : animation-fill-mode  does not exist in CSS3.0 ... 

So is that a bug  ? ... cause clearly the fill-mode is a CSS3.0 property .. 

thankx , 

# Csharper ;)