var is=new function()
{ 	
	this.VER=navigator.appVersion;
	this.AGENT=navigator.userAgent;
	this.DOM=(document.getElementById)?1:0;
	this.IE4=(document.all&&!this.DOM)?1:0;
	this.IE5=(this.VER.indexOf("MSIE 5")>-1&&this.DOM)?1:0; 
	this.IE6=(this.VER.indexOf("MSIE 6")>-1&&this.DOM)?1:0;
	this.IE7=(this.VER.indexOf("MSIE 7")>-1&&this.DOM)?1:0;
	this.IE=(this.IE4||this.IE5||this.IE6||this.IE7)?1:0;	
	this.MAC=this.AGENT.indexOf("Mac")>-1;
	this.NS6=(document.getElementById&&!document.all)?1:0;
	this.NS4=(document.layers&&!this.DOM)?1:0;
	this.NS=(this.NS6||this.NS4)?1:0;
	this.OPERA=this.AGENT.indexOf("Opera")>-1;
	return this;
};
function getElement(id)
{
	if(is.DOM)
	{
		return document.getElementById(id);
	}
	else if(is.IE)
	{
		return eval("document.all."+id);
	}
	else if(is.NS)
	{
		return eval("document."+id);
	};
};
function toggleDisplay(id)
{
	var obj = getElement(id);

	if(obj == undefined)
		return false;

	obj.style['display'] = obj.style['display'] == 'block' ? 'none' : 'block';

	return false;
};