function BrowserSystemCheck() {
	var brwtype = navigator.appName
	if (brwtype=="Netscape") this.brwtype = "ns"
	else if (brwtype=="Microsoft Internet Explorer") this.brwtype = "ie"
	else this.brwtype = brwtype
	this.brwvers = navigator.appVersion
	this.brwversion = parseInt(this.brwvers)
		
	this.ns = (this.brwtype=="ns" && this.brwversion>=4)
	this.ns4 = (this.brwtype=="ns" && this.brwversion==4)
	this.ns6 = (this.brwtype=="ns" && this.brwversion==5)
	this.ie = (this.brwtype=="ie" && this.brwversion>=4)
	this.ie4 = (this.brwvers.indexOf('MSIE 4')>0)
	this.ie5 = (this.brwvers.indexOf('MSIE 5')>0)
	this.min = (this.ns||this.ie)
	
	this.winos = (this.brwvers.lastIndexOf('Win')!= -1)
	this.macos = (this.brwvers.lastIndexOf('Win') == -1)
	this.linux_unix = (this.brwvers.lastIndexOf('X11') != -1)
	this.macosie = this.macos && this.ie
	this.macosns = this.macos && this.ns
	this.winosie = this.winos && this.ie
	this.winosns = this.winos && this.ns
	this.linux_unixns = this.linux_unix && this.ns
}

    var is
	is = new BrowserSystemCheck()