mysql>  SHOW VARIABLES LIKE 'char%';
	+--------------------------+----------------------------+
	| Variable_name            | Value                      |
	+--------------------------+----------------------------+
	| character_set_client     | utf8                       |
	| character_set_connection | utf8                       |
	| character_set_database   | utf8                       |
	| character_set_filesystem | binary                     |
	| character_set_results    | utf8                       |
	| character_set_server     | utf8                       |
	| character_set_system     | utf8                       |
	| character_sets_dir       | /usr/share/mysql/charsets/ |
	+--------------------------+----------------------------+
	8 rows in set (0.00 sec)
	 
	mysql> SHOW VARIABLES LIKE 'coll%';
	+----------------------+-----------------+
	| Variable_name        | Value           |
	+----------------------+-----------------+
	| collation_connection | utf8_general_ci |
	| collation_database   | utf8_general_ci |
	| collation_server     | utf8_general_ci |
	+----------------------+-----------------+
	3 rows in set (0.00 sec)
	 
	 
	mysql> show table status from データベース名 ;
	+-------------------------------------+--------+---------+------------+-------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| Name                                | Engine | Version | Row_format | Rows  | Avg_row_length | Data_length | Max_data_length  | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation       | Checksum | Create_options | Comment |
	+-------------------------------------+--------+---------+------------+-------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| テーブルB            | MyISAM |      10 | Dynamic    |  3674 |             39 |      145564 |  281474976710655 |        39936 |         0 |           NULL | 2012-05-30 13:20:52 | 2012-05-30 13:20:52 | NULL       | utf8_general_ci |     NULL |                |         |
	| テーブルA                               | InnoDB |      10 | Compact    |   145 |            451 |       65536 |                0 |        49152 |  45088768 |            172 | 2012-05-28 18:42:27 | NULL                | NULL       | utf8_unicode_ci |     NULL |                |         |
	+-------------------------------------+--------+---------+------------+-------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	56 rows in set (0.02 sec)
	 
	あーーーーーーーーーーー。
	 
	テーブルB = utf8_general_ci
	テーブルA = utf8_unicode_ci
	 
	やっと、見えた。
	システムAのテーブルはutf8_unicode_ciだけど、システムBはutf8_general_ciだ。
	 
	ALTER TABLE `テーブルB` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci; 
	 
	mysql> show table status from データベース名 like "テーブルB";
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| Name                     | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation       | Checksum | Create_options | Comment |
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| テーブルB | MyISAM |      10 | Dynamic    | 3674 |             39 |      145564 | 281474976710655 |        39936 |         0 |           NULL | 2012-05-30 14:02:45 | 2012-05-30 14:02:45 | NULL       | utf8_unicode_ci |     NULL |                |         |
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	1 row in set (0.00 sec)
	 
	修正できたー。
	ついでに他のシステムB系テーブルも変更して、統一する。
	 
	これで、いけるはず。
	 
	mysql>  SELECT c.カラムB FROM テーブルA r, テーブルB c WHERE r.カラムA = c.カラムB;
	ERROR 1267 (HY000): Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '='
	 
	あれー?
	 
	mysql> show table status from データベース名 like "テーブルA";
	+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+
	| Name  | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time | Check_time | Collation       | Checksum | Create_options | Comment |
	+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+
	| テーブルA | InnoDB |      10 | Compact    |  145 |            451 |       65536 |               0 |        49152 |  45088768 |            172 | 2012-05-28 18:42:27 | NULL        | NULL       | utf8_unicode_ci |     NULL |                |         |
	+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+
	 
	mysql> show table status from データベース名 like "テーブルB";
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| Name                     | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time         | Check_time | Collation       | Checksum | Create_options | Comment |
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	| テーブルB | MyISAM |      10 | Dynamic    | 3674 |             39 |      145564 | 281474976710655 |        39936 |         0 |           NULL | 2012-05-30 14:02:45 | 2012-05-30 14:02:45 | NULL       | utf8_unicode_ci |     NULL |                |         |
	+--------------------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
	1 row in set (0.00 sec)
	 
	 
	なんか適用されてないっぽい?
	 
	 
	んー、とりあえず、Mysqlの再起動。
	 
	# /etc/rc.d/init.d/mysqld restart
	mysqld を停止中:                                           [  OK  ]
	mysqld を起動中:                                           [  OK  ]
	 
	 
	で、再度。
	 
	mysql> SELECT c.カラムB FROM テーブルA r, テーブルB c WHERE r.カラムA = c.カラムB;
	ERROR 1267 (HY000): Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '='
	 
	 
	 
	えー・・・・・・・・・
	やっぱりdumpするしかないのかー・・・
	 
	# mysqldump -u root -p データベース名 > dump_データベース名_20120530.sql
	Enter password:
	 
	[1]+  停止                  mysqldump -u root -p admin
	 
	vi で編集。
	 
	カラムBを使用している箇所のみ、
	 
	COLLATE utf8_unicode_ci
	 
	に変更
	 
	これで復元する。
	# mysql -u root -p データベース名 < dump_データベース名_20120530.sql
	 
	やっと解決しましたー。
	 
	以下、参考URL