insert timestamp failure with 0000-00-00 00:00:00.000000 in prepare statement

[lysu]

1. What did you do?

    CREATE TABLE timestamp_insert ( id INT NOT NULL PRIMARY KEY, tstamp TIMESTAMP NOT NULL )

then prepare and exec a insert 0000-00-00 00:00:00.000000 into tstamp

    stmt= const_cast<char *>("INSERT INTO timestamp_insert ( id, tstamp ) VALUES ( ?, ? )");
    if(mysql_stmt_prepare(mysql_stmt, stmt, strlen(stmt)))
    {
        my_chk_stmt(&mysql, mysql_stmt, __LINE__);
    }

    memset(mysql_bind_param, 0, sizeof(mysql_bind_param));
    mysql_bind_param[0].buffer_type= MYSQL_TYPE_LONG;
    mysql_bind_param[0].buffer= (char*)&id;
    mysql_bind_param[0].is_null= 0;
    mysql_bind_param[0].length= 0;
    mysql_bind_param[1].buffer_type= MYSQL_TYPE_TIMESTAMP;
    mysql_bind_param[1].buffer= &tstamp;
    mysql_bind_param[1].is_null= 0;
    mysql_bind_param[1].length= 0;
    if(mysql_stmt_bind_param(mysql_stmt, mysql_bind_param))
    {
        my_chk_stmt(&mysql, mysql_stmt, __LINE__);
    }

    id= 2;
    tstamp.year= 0;
    tstamp.month= 0;
    tstamp.day= 0;
    tstamp.hour= 0;
    tstamp.minute= 0;
    tstamp.second= 0;
    tstamp.second_part= 0;

    if(mysql_stmt_execute(mysql_stmt))
    {
        my_chk_stmt(&mysql, mysql_stmt, __LINE__);
    }

2. What did you expect to see?

success

3. What did you see instead?

1292 : invalid time format: '0'

4. What version of TiDB are you using (tidb-server -V or run select tidb_version(); on TiDB)?

2.1.0.rc1