こんにちは、兵頭です。
既存のテーブルに新しいカラムを追加するＳＱＬ文をphpmyadmin上から
実行すると、１，２分ほどしてから以下のメッセージを出力してサービスが停止します。 

「SHOW TABLE STATUS LIKE 'テーブルA'
#2003-サーバが応答しません。」

OS:windows2003
MySQL：4.0.26

全てのテーブルについてエラーになるわけではなく、一部のテーブルのみ現象が発生します。
現象がおきているのをテーブルA,テーブルBとすると、
テーブルAはレコード件数は９０万件弱ですが、カラム数が２００以上あります。
テーブルBはレコード件数が７００万件近くあります。

カラムの追加は３つあり、一つのSQL文で３つを追加しようとしています。
全てのカラムは既存の最後に追加します。
データ型は全てINT(20)です。
以下はエラーログです。

***  Windows2003　アプリログ　************************************************
エラー発生アプリケーション mysqld-nt.exe、
バージョン 0.0.0.0、
エラー発生モジュール mysqld-nt.exe、
バージョン 0.0.0.0、
エラー発生アドレス 0x00173539

***  mysqlエラーログ　　*******【】内は適当に置き換えています*********************
=====================================
070702 10:25:12 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 16 seconds
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 14700, signal count 14621
Mutex spin waits 46050, rounds 242751, OS waits 2178
RW-shared spins 9815, OS waits 4912; RW-excl spins 7452, OS waits 6393
------------
TRANSACTIONS
------------
Trx id counter 0 292124530
Purge done for trx's n:o < 0 292124528 undo n:o < 0 0
Total number of lock structs in row lock hash table 155868
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0 292124472, ACTIVE 137 sec, OS thread id 2344 inserting, 
thread declared inside InnoDB 141
mysql tables in use 2, locked 3
155871 lock struct(s), heap size 7515456, undo log entries 820591
MySQL thread id 555, query id 151994 【サーバ名】.【ドメイン名】.local 【IPアドレス】　user copy to tmp table
ALTER TABLE `【テーブルA】` ADD `【追加カラム１】` INT( 20 ) NOT NULL ,

ADD `【追加カラム２】` INT( 20 ) NOT NULL ,

ADD `【追加カラム３】` INT( 20 ) NOT NULL
--------
FILE I/O
--------
I/O thread 0 state: wait Windows aio (insert buffer thread)
I/O thread 1 state: wait Windows aio (log thread)
I/O thread 2 state: wait Windows aio (read thread)
I/O thread 3 state: wait Windows aio (write thread)
Pending normal aio reads: 0, aio writes: 0,
 ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0
Pending flushes (fsync) log: 0; buffer pool: 0
140455 OS file reads, 135743 OS file writes, 8784 OS fsyncs
993.19 reads/s, 16384 avg bytes/read, 1093.12 writes/s, 115.62 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf for space 0: size 194, free list len 109, seg size 304,
593652 inserts, 546301 merged recs, 7604 merges
Hash table size 34679, used cells 1, node heap has 1 buffer(s)
3625.21 hash searches/s, 9780.83 non-hash searches/s
---
LOG
---
Log sequence number 4 3450941386
Log flushed up to   4 3450941368
Last checkpoint at  4 3449305499
0 pending log writes, 0 pending chkp writes
5792 log i/o's done, 41.87 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total memory allocated 14116366; in additional pool allocated 1045760
Buffer pool size   512
Free buffers       32
Database pages     21
Modified db pages  5
Pending reads 1
Pending writes: LRU 0, flush list 0, single page 0
Pages read 140317, created 60891, written 126051
993.56 reads/s, 132.24 creates/s, 1012.37 writes/s
Buffer pool hit rate 982 / 1000
--------------
ROW OPERATIONS
--------------
1 queries inside InnoDB, 0 queries in queue
Main thread id 2692, state: sleeping
Number of rows inserted 935034, updated 53, deleted 0, read 2159111
1819.95 inserts/s, 0.00 updates/s, 0.00 deletes/s, 3142.43 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================
070702 10:53:20  InnoDB: Database was not shut down normally.
InnoDB: Starting recovery from log files...
InnoDB: Starting log scan based on checkpoint at
InnoDB: log sequence number 4 3453608225
InnoDB: Doing recovery: scanned up to log sequence number 4 3455236442
InnoDB: 1 transaction(s) which must be rolled back or cleaned up
InnoDB: in total 824486 row operations to undo
InnoDB: Trx id counter is 0 292124928
070702 10:53:20  InnoDB: Starting an apply batch of log records to the 
database...
InnoDB: Progress in percents: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 
44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 
69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 
94 95 96 97 98 99
InnoDB: Apply batch completed
InnoDB: Starting rollback of uncommitted transactions
InnoDB: Rolling back trx with id 0 292124472, 824486 rows to undo
InnoDB: Progress in percents: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 
44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 
69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 
94 95 96 97 98 99 100
InnoDB: Rolling back of trx id 0 292124472 completed
InnoDB: Rollback of uncommitted transactions completed
070702 10:55:14  InnoDB: Flushing modified pages from the buffer pool...
070702 10:55:14  InnoDB: Started
MySql: ready for connections.
Version: '4.0.26-nt'  socket: ''  port: 3306  Official MySQL binary
070702 12:03:19 MySql: Normal shutdown

070702 12:03:28 MySql: Forcing close of thread 1  user: 'ODBC'
*******************************************************************************


どなたかお分かりになる方、おられましたらご教授お願いします。

兵頭