public function Sign($cert_filename, $key_filename, $key_pass) {
    $this->sign_cert_file = $cert_filename;
    $this->sign_key_file = $key_filename;
    $this->sign_key_pass = $key_pass;
  }
public function Sign($cert_filename, $key_filename, $key_pass) {
    $this->sign_cert_file = $cert_filename;
    $this->sign_key_file = $key_filename;
    $this->sign_key_pass = $key_pass;
  }
public function Sign ( $ cert_filename , $ key_filename , $ key_pass ) { $ this -> sign_cert_file = $ cert_filename ; $ this -> sign_key_file = $ key_filename ; $ this -> sign_key_pass = $ key_pass ; }
Set the private key file and password to sign the message.

@access public
@param string $key_filename Parameter File Name
@param string $key_pass Password for private key
Set the private key file and password to sign the message .