您需要在 Magentos admin->system->configuration-> 中输入 .domain.com;web->cookie 域.就像 erickthered 提到的那样，您需要将 cookie 提供给您的其他子域才能被读取.这对于所有网络应用程序都是一样的.

You will need to enter in .domain.com in Magentos admin->system->configuration->web->cookie domain. Like erickthered mentioned, you will need to make the cookie available to your other subdomains in order for it to be read. This is the same with all web applications.

参考:http://www.magentocommerce.com/wiki/modules_reference/english/mage_adminhtml/system_config/edit/web#session_cookie_management_field_descriptions