120509 14:30:45 [Note] Plugin 'FEDERATED' is disabled.
InnoDB: The user has set SRV_FORCE_NO_LOG_REDO on
InnoDB: Skipping log redo
120509 14:30:45  InnoDB: Started; log sequence number 0 0
InnoDB: !!! innodb_force_recovery is set to 6 !!!
120509 14:30:45 [Note] Event Scheduler: Loaded 0 events
120509 14:30:45 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.1.41-3ubuntu12'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu)
120509 14:30:59 - mysqld got signal 11 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help diagnose
the problem, but since we have already crashed, something is definitely wrong
and this may fail.

key_buffer_size=16777216
read_buffer_size=131072
max_used_connections=1
max_threads=151
threads_connected=1
It is possible that mysqld could use up to 
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 345919 K
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

thd: 0xb9528a10
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 0xb20c836c thread_stack 0x30000
/usr/sbin/mysqld(my_print_stacktrace+0x2d) [0xb76fd30d]
/usr/sbin/mysqld(handle_segfault+0x494) [0xb73c93d4]
[0xb7144400]
/usr/sbin/mysqld(ha_innobase::innobase_initialize_autoinc()+0x46) [0xb75a0416]
/usr/sbin/mysqld(ha_innobase::open(char const*, int, unsigned int)+0x379) [0xb75a8099]
/usr/sbin/mysqld(handler::ha_open(st_table*, char const*, int, int)+0x43) [0xb74d4443]
/usr/sbin/mysqld(open_table_from_share(THD*, st_table_share*, char const*, unsigned int, unsigned int, unsigned int, st_table*, bool)+0x5c5) [0xb7426ae5]
/usr/sbin/mysqld(+0x2bde5d) [0xb741fe5d]
/usr/sbin/mysqld(open_table(THD*, TABLE_LIST*, st_mem_root*, bool*, unsigned int)+0x9f2) [0xb7421212]
/usr/sbin/mysqld(open_tables(THD*, TABLE_LIST**, unsigned int*, unsigned int)+0x71e) [0xb7421f2e]
/usr/sbin/mysqld(open_and_lock_tables_derived(THD*, TABLE_LIST*, bool)+0x4e) [0xb742215e]
/usr/sbin/mysqld(mysql_execute_command(THD*)+0x17f0) [0xb73dd370]
/usr/sbin/mysqld(mysql_parse(THD*, char const*, unsigned int, char const**)+0x3ae) [0xb73e3fce]
/usr/sbin/mysqld(dispatch_command(enum_server_command, THD*, char*, unsigned int)+0x11ce) [0xb73e51ae]
/usr/sbin/mysqld(do_command(THD*)+0xf3) [0xb73e6063]
/usr/sbin/mysqld(handle_one_connection+0x2a0) [0xb73d4bc0]
/lib/libpthread.so.0(+0x57f0) [0xb71297f0]
/lib/libc.so.6(clone+0x5e) [0xb6f023de]
Trying to get some variables.
Some pointers may be invalid and cause the dump to abort...
thd->query at 0xb9573ef0 = LOCK TABLES `SystemEvents` READ /*!32311 LOCAL */,`SystemEventsProperties` READ /*!32311 LOCAL */
thd->thread_id=1
thd->killed=NOT_KILLED
The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
120509 14:30:59 [Note] Plugin 'FEDERATED' is disabled.
InnoDB: The user has set SRV_FORCE_NO_LOG_REDO on
InnoDB: Skipping log redo
120509 14:30:59  InnoDB: Started; log sequence number 0 0
InnoDB: !!! innodb_force_recovery is set to 6 !!!
120509 14:30:59 [Note] Event Scheduler: Loaded 0 events
120509 14:30:59 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.1.41-3ubuntu12'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu)
120509 14:31:14 [Note] /usr/sbin/mysqld: Normal shutdown

120509 14:31:14 [Note] Event Scheduler: Purging the queue. 0 events
120509 14:31:14  InnoDB: Starting shutdown...
120509 14:31:15  InnoDB: Shutdown completed; log sequence number 0 8204
120509 14:31:15 [Note] /usr/sbin/mysqld: Shutdown complete