Javascript not working in firefox window but is working firefox mac

1

Im having a problem that I can not seem to find any information for. I have javascript that calls an actionscript function in a flash file on the same page. The javascript works correctly in firefox on the mac and IE but will not work properly on firefox in windows.

This is the function that is called via an image map link

function departmentsHTML(){
		document.getElementById("flash").style.zIndex = "-1";
		document.getElementById("background").style.zIndex = "999";
		getSWF('homepage').departmentsHTML();
	}

this is the getSWF function

function getSWF(movieName) {
    if (navigator.appName.indexOf("Microsoft") != -1) {
        return window[movieName];
    }
    else {
      if(document[movieName].length != undefined){
          return document[movieName][1];
      }
        return document[movieName];
    }
}

This is the image map

<map name="Map" id="Map"><area shape="rect" coords="62,18,90,492" alt="Department"  href="javascript:departmentsHTML()" onclick="getSWF('homepage').departmentsHTML();"/>
</map>

as you can see in the image map I have tried calling the javascript on the page and the actionscript function directly. I have tried a few different things on the map actions as well

Any help would be appreciated.