Gradient baggrund med CSS - firefox/mac problem

Hej, jeg skal lave en gradient baggrund på en menu, som ikke må indeholde et baggrundsbillede og det skal virke i Firefox. Jeg har det til at virke i IE men Firefox driller og strækker det underligt. Håber nogen kan hjælpe.

KODE:
___________________________
På selve siden;
<div class="gradient FFFFFF CDCDCD vertical bar">

Koden;
/*************************

Cross Browser Gradient Backgrounds
v1.0
Last Revision: 11.03.2005
steve@slayeroffice.com

please leave this notice in tact.

should you improve upon this code, please
let me know so that I may update the version
hosted on slayeroffice

--- to use --
reference this file (on your own server) as a javascript src
in the head of your document. give the elements
you want a gradient background applied to a class as such:

class="gradient 000000 ffffff horizontal"

See http://slayeroffice.com/code/gradient/ for more examples.


*************************/

window.addEventListener?window.addEventListener("load",createGradient,false):window.attachEvent("onload",createGradient);

function createGradient() {
    if(!document.getElementById)return;
   
    objArray = getGradientObjects();
    if(!objArray.length) return;
   
    for(i=0;i<objArray.length;i++) {
        params = objArray[i].className.split(" ");
        if(document.all && !window.opera) {
            objArray[i].style.width = objArray[i].offsetWidth + "px";
            params[3] == "horizontal"?gType = 1:gType = 0;
            objArray[i].style.filter = "progid:DXImageTransform.Microsoft.Gradient(GradientType="+gType+",StartColorStr=\"#" + params[1] + "\",EndColorStr=\"#" + params[2] + "\")";
    } else {
            colorArray = createColorPath(params[1],params[2]);
            x=0;y=0;
            if(params[3] == "horizontal") {
                w=Math.round(objArray[i].offsetWidth/colorArray.length);
                if(!w)w=1;
                h = objArray[i].offsetHeight;
            } else {
                h = Math.round(objArray[i].offsetHeight/colorArray.length);
                if(!h) h =1;
                w = objArray[i].offsetWidth;
            }
            makeGrandParent(objArray[i]);
            tmpDOM = document.createDocumentFragment();
            for(p=0;p<colorArray.length;p++) {
                g = document.createElement("div");
                g.setAttribute("style","position:absolute;z-index:0;top:" + y + "px;left:" + x + "px;height:" + h + "px;width:" + w + "px;background-color:rgb(" + colorArray[p][0] + "," + colorArray[p][1] + "," + colorArray[p][2] + ");");
                params[3] == "horizontal"?x+=w:y+=h;
                tmpDOM.appendChild(g);
                if(y>=objArray[i].offsetHeight || x >= objArray[i].offsetWidth) break;
            }
            objArray[i].appendChild(tmpDOM);
            tmpDOM = null;
        }
    }
}

function getGradientObjects() {
    a = document.getElementsByTagName("*");
    objs = new Array();
    for(i=0;i<a.length;i++) {
        c = a[i].className;
        if(c != "") if(c.indexOf("gradient") == 0) objs[objs.length] = a[i];
    }
    return objs;
}
   
function createColorPath(color1,color2) {
    colorPath = new Array();
    colorPercent = 1.0;
    do {
        colorPath[colorPath.length]=setColorHue(longHexToDec(color1),colorPercent,longHexToDec(color2));
        colorPercent-=.01;
    } while(colorPercent>0);
    return colorPath;
}
       
function setColorHue(originColor,opacityPercent,maskRGB) {
    returnColor=new Array();
    for(w=0;w<originColor.length;w++) returnColor[w] = Math.round(originColor[w]*opacityPercent) + Math.round(maskRGB[w]*(1.0-opacityPercent));
    return returnColor;
}

function longHexToDec(longHex) {
    return new Array(toDec(longHex.substring(0,2)),toDec(longHex.substring(2,4)),toDec(longHex.substring(4,6)));   
}

function toDec(hex) {   
    return parseInt(hex,16);
}
   
function makeGrandParent(obj) {
    disp = document.defaultView.getComputedStyle(obj,'').display;
    disp == "block"?nSpan = document.createElement("div"):    nSpan = document.createElement("span");
    mHTML = obj.innerHTML;
    obj.innerHTML = "";
    nSpan.innerHTML = mHTML;
    nSpan.setAttribute("style","position:relative;z-index:10;");
    obj.appendChild(nSpan);
}