Comment 7 for bug 1071909

seems to got me also. i attach the files you asked to angelo doing 'ls -l /var/log/mysql*

there was the /var/log/mysql/error.log

130314 12:21:13 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:13 InnoDB: The InnoDB memory heap is disabled
130314 12:21:13 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:13 InnoDB: Compressed tables use zlib 1.2.3.4
130314 12:21:13 InnoDB: Initializing buffer pool, size = 128.0M
130314 12:21:13 InnoDB: Completed initialization of buffer pool
InnoDB: The first specified data file ./ibdata1 did not exist:
InnoDB: a new database to be created!
130314 12:21:13 InnoDB: Setting file ./ibdata1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
130314 12:21:13 InnoDB: Log file ./ib_logfile0 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile0 size to 5 MB
InnoDB: Database physically writes the file full: wait...
130314 12:21:14 InnoDB: Log file ./ib_logfile1 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile1 size to 5 MB
InnoDB: Database physically writes the file full: wait...
InnoDB: Doublewrite buffer not found: creating new
InnoDB: Doublewrite buffer created
InnoDB: 127 rollback segment(s) active.
InnoDB: Creating foreign key constraint system tables
InnoDB: Foreign key constraint system tables created
130314 12:21:15 InnoDB: Waiting for the background threads to start
130314 12:21:16 InnoDB: 1.1.8 started; log sequence number 0
130314 12:21:16 InnoDB: Starting shutdown...
130314 12:21:17 InnoDB: Shutdown completed; log sequence number 1595675
130314 12:21:17 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:17 InnoDB: The InnoDB memory heap is disabled
130314 12:21:17 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:17 InnoDB: Compressed tables use zlib 1.2.3.4
130314 12:21:17 InnoDB: Initializing buffer pool, size = 128.0M
130314 12:21:17 InnoDB: Completed initialization of buffer pool
130314 12:21:17 InnoDB: highest supported file format is Barracuda.
130314 12:21:17 InnoDB: Waiting for the background threads to start
130314 12:21:18 InnoDB: 1.1.8 started; log sequence number 1595675
130314 12:21:18 InnoDB: Starting shutdown...
130314 12:21:18 InnoDB: Shutdown completed; log sequence number 1595675
130314 12:21:18 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:18 InnoDB: The InnoDB memory heap is disabled
130314 12:21:18 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:18 InnoDB: Compressed tables use zlib 1.2.3.4
130314 12:21:18 InnoDB: Initializing buffer pool, size = 128.0M
130314 12:21:18 InnoDB: Completed initialization of buffer pool
130314 12:21:18 InnoDB: highest supported file format is Barracuda.
130314 12:21:19 InnoDB: Waiting for the background threads to start
130314 12:21:20 InnoDB: 1.1.8 started; log sequence number 1595675
ERROR: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'ALTER TABLE user ADD column Show_view_priv enum('N','Y') CHARACTER SET utf8 NOT ' at line 1
130314 12:21:20 [ERROR] Aborting

130314 12:21:20 InnoDB: Starting shutdown...
130314 12:21:21 InnoDB: Shutdown completed; log sequence number 1595675
130314 12:21:21 [Note] /usr/sbin/mysqld: Shutdown complete

130314 12:21:21 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:21 InnoDB: The InnoDB memory heap is disabled
130314 12:21:21 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:21 InnoDB: Compressed tables use zlib 1.2.3.4
130314 12:21:21 InnoDB: Initializing buffer pool, size = 128.0M
130314 12:21:21 InnoDB: Completed initialization of buffer pool
130314 12:21:21 InnoDB: highest supported file format is Barracuda.
130314 12:21:21 InnoDB: Waiting for the background threads to start
130314 12:21:22 InnoDB: 1.1.8 started; log sequence number 1595675
130314 12:21:22 InnoDB: Starting shutdown...
130314 12:21:22 InnoDB: Shutdown completed; log sequence number 1595675
130314 12:21:22 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:22 InnoDB: The InnoDB memory heap is disabled
130314 12:21:22 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:22 InnoDB: Compressed tables use zlib 1.2.3.4
130314 12:21:22 InnoDB: Initializing buffer pool, size = 128.0M
130314 12:21:22 InnoDB: Completed initialization of buffer pool
130314 12:21:22 InnoDB: highest supported file format is Barracuda.
130314 12:21:22 InnoDB: Waiting for the background threads to start
130314 12:21:23 InnoDB: 1.1.8 started; log sequence number 1595675
ERROR: 1050 Table 'plugin' already exists
130314 12:21:23 [ERROR] Aborting

130314 12:21:23 InnoDB: Starting shutdown...
130314 12:21:24 InnoDB: Shutdown completed; log sequence number 1595675
130314 12:21:24 [Note] /usr/sbin/mysqld: Shutdown complete

130314 12:21:25 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:25 InnoDB: The InnoDB memory heap is disabled
130314 12:21:25 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:25 InnoDB: Compressed tables use zlib 1.2.3.4
/usr/sbin/mysqld: Can't create/write to file '/tmp/ibxcUqHO' (Errcode: 13)
130314 12:21:25 InnoDB: Error: unable to create temporary file; errno: 13
130314 12:21:25 [ERROR] Plugin 'InnoDB' init function returned error.
130314 12:21:25 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
130314 12:21:25 [ERROR] Unknown/unsupported storage engine: InnoDB
130314 12:21:25 [ERROR] Aborting

130314 12:21:25 [Note] /usr/sbin/mysqld: Shutdown complete

130314 12:21:26 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:26 InnoDB: The InnoDB memory heap is disabled
130314 12:21:26 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:26 InnoDB: Compressed tables use zlib 1.2.3.4
/usr/sbin/mysqld: Can't create/write to file '/tmp/ibsr4u0T' (Errcode: 13)
130314 12:21:26 InnoDB: Error: unable to create temporary file; errno: 13
130314 12:21:26 [ERROR] Plugin 'InnoDB' init function returned error.
130314 12:21:26 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
130314 12:21:26 [ERROR] Unknown/unsupported storage engine: InnoDB
130314 12:21:26 [ERROR] Aborting

130314 12:21:26 [Note] /usr/sbin/mysqld: Shutdown complete

130314 12:21:27 [Note] Plugin 'FEDERATED' is disabled.
130314 12:21:27 InnoDB: The InnoDB memory heap is disabled
130314 12:21:27 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130314 12:21:27 InnoDB: Compressed tables use zlib 1.2.3.4
/usr/sbin/mysqld: Can't create/write to file '/tmp/ibjms7j7' (Errcode: 13)
130314 12:21:27 InnoDB: Error: unable to create temporary file; errno: 13
130314 12:21:27 [ERROR] Plugin 'InnoDB' init function returned error.
130314 12:21:27 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
130314 12:21:27 [ERROR] Unknown/unsupported storage engine: InnoDB
130314 12:21:27 [ERROR] Aborting

130314 12:21:27 [Note] /usr/sbin/mysqld: Shutdown complete

hope this helps

trying now sudo apt-get upgrade and see what happens