rsgallery2_legacy_1.14.3 上传文件报错

Joomla1.51 Xampp环境,前后台均正常,安装rsgallery2也正常,legacy模式打开.
上传图片(格式JPG,很小).报错:
Fatal error: Call to undefined function mysql_real_escape_string() in D:\xampp\htdocs\sunlord\administrator\components\com_rsgallery2\includes\img.utils.php on line 176
咋回事呢??  谢谢指教!!