function browcheck(){ 
	this.ver=navigator.appVersion;
	this.dom=document.getElementById?1:0;
	this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
	this.ie50=(this.ver.indexOf("MSIE 5.0")>-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.ie4=(document.all && !this.dom)?1:0;
	this.ie=this.ie4||this.ie5||this.ie6||this.ie7;
	this.ns5=(this.dom && parseInt(this.ver) >= 5) ?1:0; 
	this.ns4=(document.layers && !this.dom)?1:0;
	this.ns=this.ns4||this.ns5;
	this.bw=(this.ie5 || this.ie4 || this.ie6 || this.ie7 || this.ns4 || this.ns5);
	return this;
}
function getOS(){
	this.os = navigator.userAgent.toLowerCase();
	this.mac = (( this.os.indexOf( "ppc" ) !=-1 ) || (this.os.indexOf( "powerpc" ) !=-1 )) ? 1 : 0;

return
}
var bw = new browcheck();
os=new getOS();