What Is Invalid In This Code ?, That Hinders Cross

What is invalid in this CSS that hinders it to show up the edge effect (ripped papper like on left & right side) in Mozilla FireFox Where as Internet Explorer shows it out perfectly....

Problematic URL: http://ajaysekher.net/

This is a CSS effect made by casecading a picture repeatedly in Y axis in the background of a column.... I am attaching the Screenshot of it showing the edges perfectly in IE also the CSS code used for that effect. Astonishingly the CSS and the XHTML code is said to be valid by W3.ORG..... Adding the validation result URLs too....

Can any one figure out the reason for cross browser incompatibility in this code....


CSS CODE:

.shadowleft {
background-attachment: fixed;
background-image: url('edge_left.gif');
background-repeat: repeat-y;
background-position: right top;
}
.shadowright {
background-attachment: fixed;
background-image: url('edge_right.gif');
background-repeat: repeat-y;
background-position: left top;
}

Your url doesn't work. So I guess nobody can really see what the problem is. Besides, Firefox doesn't always display stuff properly even if you have "validated" code. It could be a bug.. One time I had a div and tried to change the height but no matter what number I put in there it didn't change. I eventually, just put one line in the html that just showed the div with a border and it still didn't work.

background-image: url(edge_left.gif) fixed;I don't know but thats what I think it's probably wrong. Im no good at solving html/css problems unless it's mine ^^

post the whole code and we will write you correct answer...i am good in solving those problems....