mysql> SELECT t1.login, t1.value as city, t2.value as regdate, t3.value as email FROM `tst` t1
    -> LEFT JOIN `tst` t2 ON t1.login = t2.login AND t2.param='regdate'
    -> LEFT JOIN `tst` t3 ON t1.login = t3.login AND t3.param='email'
    -> GROUP BY t1.login;
+-------+--------+------------+-----------------+
| login | city   | regdate    | email           |
+-------+--------+------------+-----------------+
| Alex  | London | 22-04-2009 | aswer@yahoo.com | 
| Nata  | Paris  | 15-07-2009 | dser@mail.com   | 
+-------+--------+------------+-----------------+
2 rows in set (0,00 sec)

mysql> SELECT login,
    -> (SELECT `value` FROM `tst` WHERE `login`=t1.login AND `param`='city') as city,
    -> (SELECT `value` FROM `tst` WHERE `login`=t1.login AND `param`='regdate') as regdate,
    -> (SELECT `value` FROM `tst` WHERE `login`=t1.login AND `param`='email') as email
    -> FROM `tst` t1
    -> GROUP BY `login`;
+-------+--------+------------+-----------------+
| login | city   | regdate    | email           |
+-------+--------+------------+-----------------+
| Alex  | London | 22-04-2009 | aswer@yahoo.com | 
| Nata  | Paris  | 15-07-2009 | dser@mail.com   | 
+-------+--------+------------+-----------------+
2 rows in set (0,01 sec)