function lib_bwcheck()
{
	this.ver=navigator.appVersion;
	this.agent=navigator.userAgent;
	this.opera=navigator.userAgent.indexOf("Opera")>-1 ? 1 : 0;
	this.ie5=(this.ver.indexOf("MSIE 5")>-1 && !this.opera) ? 1 : 0;
	this.ie6=(this.ver.indexOf("MSIE 6")>-1 && !this.opera) ? 1 : 0;
	this.ie7=(this.ver.indexOf("MSIE 7")>-1 && !this.opera) ? 1 : 0;
	this.ie=this.ie5||this.ie6||this.ie7;
	this.mac=this.agent.indexOf("Mac")>-1;
	return this;
}
var bw=lib_bwcheck();