This is a ERR file from my MySQL Server (clean installation):
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090727 15:36:01 [Note] Plugin 'FEDERATED' is disabled.
InnoDB: The first specified data file .\ibdata1 did not exist:
InnoDB: a new database to be created!
090727 15:36:02  InnoDB: Setting file .\ibdata1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
090727 15:36:02  InnoDB: Log file .\ib_logfile0 did not exist: new to be created
InnoDB: Setting log file .\ib_logfile0 size to 10 MB
InnoDB: Database physically writes the file full: wait...
090727 15:36:02  InnoDB: Log file .\ib_logfile1 did not exist: new to be created
InnoDB: Setting log file .\ib_logfile1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
InnoDB: Doublewrite buffer not found: creating new
InnoDB: Doublewrite buffer created
InnoDB: Creating foreign key constraint system tables
InnoDB: Foreign key constraint system tables created
090727 15:36:03  InnoDB: Started; log sequence number 0 0
090727 15:36:03 [Note] Event Scheduler: Loaded 0 events
090727 15:36:03 [Note] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: ready for connections.
Version: '5.1.36-community'  socket: ''  port: 3306  MySQL Community Server (GPL)
090727 15:39:55 [Note] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: Normal shutdown

090727 15:39:55 [Note] Event Scheduler: Purging the queue. 0 events
090727 15:39:55  InnoDB: Starting shutdown...
090727 15:39:56  InnoDB: Shutdown completed; log sequence number 0 46409
090727 15:39:56 [Warning] Forcing shutdown of 1 plugins
090727 15:39:56 [Note] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: Shutdown complete

090727 15:40:10 [Note] Plugin 'FEDERATED' is disabled.
090727 15:40:10  InnoDB: Started; log sequence number 0 46409
090727 15:40:10 [Note] Event Scheduler: Loaded 0 events
090727 15:40:10 [Note] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: ready for connections.
Version: '5.1.36-community'  socket: ''  port: 3306  MySQL Community Server (GPL)
090727 15:43:43  InnoDB: Assertion failure in thread 2996 in file .\row\row0mysql.c line 1534
InnoDB: Failing assertion: index->type & DICT_CLUSTERED
InnoDB: We intentionally generate a memory trap.
InnoDB: Submit a detailed bug report to http://bugs.mysql.com.
InnoDB: If you get repeated assertion failures or crashes, even
InnoDB: immediately after the mysqld startup, there may be
InnoDB: corruption in the InnoDB tablespace. Please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.1/en/forcing-recovery.html
InnoDB: about forcing recovery.
090727 15:43:43 - mysqld got exception 0xc0000005 ;
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=10485760
read_buffer_size=65536
max_used_connections=3
max_threads=100
threads_connected=3
It is possible that mysqld could use up to 
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 42871 K
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

thd: 0x39937a0
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...
InnoDB: Thread 3016 stopped in file .\os\os0sync.c line 271
InnoDB: Thread 3364 stopped in file .\os\os0sync.c line 574
006B7146    mysqld.exe!row_unlock_for_mysql()[row0mysql.c:1534]
006BF358    mysqld.exe!row_search_for_mysql()[row0sel.c:4090]
006ABED0    mysqld.exe!ha_innobase::index_read()[ha_innodb.cc:4445]
0043ADB9    mysqld.exe!handler::index_read_map()[handler.h:1390]
00447F66    mysqld.exe!handler::read_range_first()[handler.cc:4184]
0044607C    mysqld.exe!handler::read_multi_range_first()[handler.cc:4058]
004D89BB    mysqld.exe!QUICK_RANGE_SELECT::get_next()[opt_range.cc:8468]
00439966    mysqld.exe!find_all_keys()[filesort.cc:564]
0043A117    mysqld.exe!filesort()[filesort.cc:245]
005B7A56    mysqld.exe!mysql_update()[sql_update.cc:419]
00557586    mysqld.exe!mysql_execute_command()[sql_parse.cc:3025]
0055BAC3    mysqld.exe!mysql_parse()[sql_parse.cc:5937]
0055C5B3    mysqld.exe!dispatch_command()[sql_parse.cc:1215]
0055D3B7    mysqld.exe!do_command()[sql_parse.cc:858]
005E0D40    mysqld.exe!handle_one_connection()[sql_connect.cc:1127]
006470BB    mysqld.exe!pthread_start()[my_winthread.c:85]
0072C633    mysqld.exe!_callthreadstart()[thread.c:293]
2E383631    
Trying to get some variables.
Some pointers may be invalid and cause the dump to abort...
thd->query at 0398CF00=UPDATE PENDENTES SET ESTACAOLOCK=12 WHERE ESTACAOLOCK=0 AND DATAMOV=15099 ORDER BY AUTOSEQUENCIAL LIMIT 1
thd->thread_id=4
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.
InnoDB: Thread 1460 stopped in file .\sync\sync0arr.c line 337
090727 15:45:04 [Note] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: Normal shutdown

090727 15:45:04 [Note] Event Scheduler: Purging the queue. 0 events
090727 15:45:06 [Warning] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: Forcing close of thread 5  user: '2412923313019'

090727 15:45:06 [Warning] C:\Arquivos de programas\MySQL\MySQL Server 5.1\bin\mysqld: Forcing close of thread 4  user: '2412923313019'

InnoDB: Thread 1616 stopped in file .\handler\ha_innodb.cc line 2262
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