Thanx for the Help!!
The result that I got is that, it doesn’t matter if your image has an alpha on it, you will have a shape with an alpha texture, meaning that your are not going to see the shape.
I had the same result using this code:
TransparencyAttributes transAtt = new TransparencyAttributes(TextureAttributes.COMBINE_REPLAXE,0.6f,TransparencyAttributes.BLEND_SRC_ALPHA,TransparencyAttributes.BLEND_SRC_ALPHA);
the alpha scale 0.6f doesn't matter.
But now I was wondering if I could see the other shape (the one that is inside) just by loading an image with an alpha on it.
Let me explain better:
In the texture of the front shape I would put an image with a draw and a part o this image just with an alpha. So then I would be able to see something of the other shape because the loaded image had an alpha on it.