type
ISC_STATUS_ARRAY=Array [0..19] of ISC_STATUS;
Tfb_database_crypt_callback = function ( status_vector: PISC_STATUS; cryptKeyCallback: ICryptKeyCallback ):ISC_STATUS;stdcall;

CryptKey = class(ICryptKeyCallbackImpl)
function callback(dataLength: Cardinal; data: Pointer; bufferLength: Cardinal; buffer: Pointer): Cardinal; override;
end;

var
  gRadugaDatabase: TIBDatabase;
  status:ISC_STATUS_ARRAY;


procedure CallFb_database_crypt_callback(status_vector: PISC_STATUS; cryptKeyCallback: ICryptKeyCallback);
  var
  hndDLLHandle: THandle;
  fb_database_crypt_callback: Tfb_database_crypt_callback;
begin
  try
    // загружаем dll динамически
    hndDLLHandle := LoadLibrary ( 'gds32.dll' );

    if hndDLLHandle <> 0 then
    begin
      // получаем адрес функции
      @fb_database_crypt_callback := getProcAddress ( hndDLLHandle,'fb_database_crypt_callback' );
      // если адрес функции найден
      if addr ( fb_database_crypt_callback ) <> nil then
      begin
       fb_database_crypt_callback (status_vector,cryptKeyCallback);
       gRadugaDatabase.Open;
      end
      else
        showMessage ( 'Function not exists...' );
    end
    else
      showMessage ( 'DLL not found...' );
  finally
    freeLibrary ( hndDLLHandle );
  end;
end;

//Вызов 
 	gRadugaDatabase.Connected := False;
        gRadugaDatabase.DatabaseName := BasePath;
        gRadugaDatabase.Params.Clear;
        gRadugaDatabase.Params.Add('user_name=' + Login);
        gRadugaDatabase.Params.Add('password=' + Password);
        gRadugaDatabase.Params.Add('lc_ctype=WIN1251');
 	CallFb_database_crypt_callback(@status,CryptKey.create);