firefox - Multiple CSS backgrounds, colour over image, ignored

Question

What's wrong with this multiple background CSS line. Firefox 4 ignores it (as it does when there's a syntax error).

background: rgba(255,0,0,0.2), url("static/menubg.jpg");

Answer 1

The solutions is using:

{-moz-linear-gradient(top, rgba(0, 0, 0, 0.5) 0%, rgba(0, 0, 0, 0.5) 100%), url(bg.png) repeat 0 0;}  

instead of:

rgba(0, 0, 0, 0.5)