Flv under mask with gaussian blur

Hi there, I need some help to realize this effect.

I have created a video for my flash application, convert it into a flv file.

Now, I have imported it into flash in a layer, then I have created a new layer where I would yo place a mask with gaussia blur. You ca see example in the pic.

I draw a mask into flash, converted it into a movieclip and assign to it a gaussian blur from the filter panel. But when I send the fla in execution (Ctrl+Enter), the video appear
through the mask, but this one have not gaussian blur filter applied.

How I have to do that? Thank you.