function exists($key) {
		$key=$this->fixheader($key);
		return isset($this->headers[$key]);
	}
function exists($key) {
		$key=$this->fixheader($key);
		return isset($this->headers[$key]);
	}
function exists ( $ key ) { $ key = $ this -> fixheader ( $ key ) ; return isset ( $ this -> headers [ $ key ] ) ; }
Return TRUE if header exists
@return bool
@param $key
Return TRUE if header exists