function lib_bcheck(){
  this.ver=navigator.appVersion;
  this.agent=navigator.userAgent;
  this.dom=document.getElementById?1:0;
  this.opera4=(this.agent.indexOf("Opera 4"))>-1;
  this.opera5=(this.agent.indexOf("Opera 5"))>-1;
  this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom && !this.opera5)?1:0;
  this.ie6=(this.ver.indexOf("MSIE 6")>-1 && this.dom && !this.opera5)?1:0;
  this.ie56=(document.createElement && this.dom && !this.opera5)?1:0;
  this.ie4=(document.all && !this.dom && !this.opera5)?1:0;
  this.ie=this.ie4||this.ie5||this.ie6 || this.ie56;
  this.mac=this.agent.indexOf("Mac")>-1;
  this.ns6=(this.agent.indexOf("Netscape/6"))>-1 && (this.dom && document.createElement) ?1:0; // gilt auch fuer mozilla
  this.ns7=(this.agent.indexOf("Netscape/7"))>-1 ;
  this.ns4=(document.layers && !this.dom)?1:0;
  this.bw=(this.ie56 || this.ie6||this.ie5||this.ie4||this.ns4||this.ns6||this.opera5);
  return this;
}
is=new lib_bcheck(); //Browsercheck object