I googled for that error and read a few threads. You could try a repair of the character_ table, e.g.:
Code:
C:\>mysql -u root 57dr1
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 5 to server version: 4.0.12-nt
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> repair table character_ ;
+------------------+--------+----------+----------+
| Table | Op | Msg_type | Msg_text |
+------------------+--------+----------+----------+
| 57dr1.character_ | repair | status | OK |
+------------------+--------+----------+----------+
1 row in set (0.01 sec)
mysql>