function replaceButtons() {
    
    var aListLft = document.getElementById('leftColumn').getElementsByTagName('li');    
    var aListRgt = document.getElementById('rightColumn').getElementsByTagName('li');
    
    var i = aListLft.length;
    var j = aListRgt.length;

    while(i--) {
        replaceButton(aListLft[i]); 
    }
    
    while(j--) {
        replaceButton(aListRgt[j]); 
    }    

}

function replaceButton(aListItem) {
    
    var a = aListItem.getElementsByTagName('a')[0];
    
    var btnId   = aListItem.id;
    var btnUrl  = a.href;
    var btnText = a.innerHTML;
    
    var so = new SWFObject("flash/button.swf", btnId, "159", "54", "8", "transparent");
    so.addParam("wmode", "transparent");
    so.addParam("menu", "false");
    so.addVariable("btn_text", btnText); 
    so.addVariable("url", btnUrl); 
    if (aListItem.className == 'overlay'){
        so.addVariable("overlay", 1);
    }                  
    so.write(btnId);  
      
}