I tried to test sending mass emails using following test code

sited form Visualforce Manual.

But failed to have received an error message.

Any suggestion appreciated.

In case of sending a singlemassage test,it was OK.

 Error Message:-

       System.EmailException:
       SendEmail failed. First exception on row 0;
       first error: INVALID_ID_FIELD,
       Visualforce templates are not currently supported for mass email.: []

 Test Code:-

    User you = [ SELECT Email
             FROM User
             WHERE Id = :UserInfo.getUserId()
             LIMIT 1 ];
    EmailTemplate template = [ SELECT Id
                           FROM EmailTemplate
                           WHERE DeveloperName = 'Test_Template'
                             LIMIT 1 ];
     Messaging.MassEmailMessage mail = new Messaging.MassEmailMessage();
     mail.templateId = template.Id;
    mail.targetObjectIds = new Id[] { you.Id };
    mail.setSaveAsActivity(false);
     Messaging.sendEmail(new Messaging.MassEmailMessage[] { mail });