function changetabOn(G,F)
{
    if(G.className.indexOf("_on") >=0)
    {
	    return;
		}
    var H=G.parentNode.id;
    var E=document.getElementById(H).getElementsByTagName("li");
    for(i=0;i<E.length;i++)
    {
        if(i==F)
        {
            G.className=H + "_on";
            if(document.getElementById(H+"_cont_"+i))
            	document.getElementById(H+"_cont_"+i).style.display="block";
        }
        else
        {
	        E[i].className=H + "_off";
	        if(document.getElementById(H+"_cont_"+i))
	        	document.getElementById(H+"_cont_"+i).style.display="none";
				}
    }
};