I know this question is quite old, however since it is unaswered and if this can help people, here is my solution to get a linear Gradient working in all mayor Browsers:
/* IE10 Consumer Preview */
background-image: -ms-linear-gradient(top, #FFFFFF 0%, #BDBDBD 100%);
/* Mozilla Firefox */
background-image: -moz-linear-gradient(top, #FFFFFF 0%, #BDBDBD 100%);
/* Opera */
background-image: -o-linear-gradient(top, #FFFFFF 0%, #BDBDBD 100%);
/* Webkit (Safari/Chrome 10) */
background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0, #FFFFFF), color-stop(1, #BDBDBD));
/* Webkit (Chrome 11+) */
background-image: -webkit-linear-gradient(top, #FFFFFF 0%, #BDBDBD 100%);
/* W3C Markup, IE10 Release Preview */
background-image: linear-gradient(to bottom, #FFFFFF 0%, #BDBDBD 100%);
There is also an onlie tool to create this CSS gradients, chek it here:
http://ie.microsoft.com/Testdrive/Graphics/CSSGradientBackgroundMaker/Default.html