The timestamp of MySQL logs only appear in the first event during that time. It means that <br /> if you have two logs within the same second, only the first one will have the timestamp.
060516 22:38:46 mysqld started
InnoDB: The first specified data file ./ibdata1 did not exist:
InnoDB: a new database to be created!
060516 22:38:54 InnoDB: Started; log sequence number 0 0
060516 22:38:54 mysqld ended
070823 20:58:09 [Note] /usr/libexec/mysqld: Shutdown complete
060516 22:38:54 [ERROR] Fatal error: Can't open privilege tables: Table 'mysql.host' doesn't exist
Connections,queries:
070823 21:00:32 1 Connect root@localhost on test1
070823 21:00:48 1 Query show tables
070823 21:00:56 1 Query select * from category
070917 16:29:01 21 Query select * from location
070917 16:29:12 21 Query select * from location where id = 1 LIMIT 1