Firefox Issue: XML brought in by Javascript coming up as null and undefined

I'm relatively new to Javascript, I've worked in Actionscript 3.0 so I kinda have the hang of syntax, but I'm having an issue with my code working in firefox.

Code:

---

function loadXML()
{   
        var article = "clientInformation.xml"
        // Load XML from a file on the web server
        if (window.ActiveXObject)
        {
                xmlDoc = new ActiveXObject('Microsoft.XMLDOM');
                xmlDoc.async="false";
                while (xmlDoc.readyState != 4) {} // readyState will be set to 4 when the document is loaded
                xmlDoc.load(article);
                displayXML();
        }
        else if (document.implementation && document.implementation.createDocument) // Broken
        {
                xmlDoc = document.implementation.createDocument("","",null);
                xmlDoc.async="false";
                xmlDoc.onload = displayXML();
                xmlDoc.load(article);
                alert("Is this happening?");
        }
       
}

//on first load
function displayXML()
{
        document.getElementById("writeup_container").innerHTML = xmlDoc.getElementsByTagName("company").item(0).text;
       
        imageURL = xmlDoc.getElementsByTagName("company")[0].attributes.getNamedItem("image").text;
        document.getElementById("image_container").innerHTML = "<img src=\"images/ClientSites/" + imageURL + "\"/>"
}

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So I have an XML file with information that I want displaying in specific DIVs but when I run it in Firefox The Alert isn't even appearing at one point I had another else alerting if the page couldn't support the script but it wasn't appearing in firefox either.

The Error I'm getting was:
Error: xmlDoc.getElementsByTagName("company").item(0) is null
Line: 34

Code:

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document.getElementById("writeup_container").innerHTML = xmlDoc.getElementsByTagName("company").item(0).text;

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So there's my problem, any help would be apprecieated, I'm not a hardcore coder so any code please explain what it does <3

The issue has been resolved for the most part I had to change the .text to .getAttribute("name");

and add this function to the loading of XML in firefox

Code:

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function loop() {
        if (document.getElementById("writeup_container").innerHTML == "")
                setTimeout("displayXML()",1000);
}

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