It seems that for login attempts - at least for username - not validated data is used. It seems that some spambots are stupid too much.
A general error occured: General Error
» SQL ERROR [ mysql4 ]

Data too long for column 'username' at row 1 [1406]

SQL

INSERT INTO phpbb3mt_login_attempts (attempt_ip, attempt_browser, attempt_forwarded_for, attempt_time, user_id, username, username_clean) VALUES ('175.44.1.77', 'Mozilla/0.6 Beta (Windows)', '', 1356020835, 0, '[url=http://www.jacketsgukijp.com/]モンクレールダウン[/url] [url=http://www.jacketsgukijp.com/]モンクレールジャケット[/url] [url=http://www.jacketsgukijp.com/]モンクレール激安[/url] [url=http://www.shoeonsalejp.com/]ナイキ シューズ[/url] [url=http://www.shoeonsalejp.com/]ナイキ ショックス[/url] [url=http://www.shoeonsalejp.com/]ナイキ 販売[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウバッグ[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウショルダーバッグ[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウアウトレット[/url]', '[url=http://www.jacketsgukijp.com/]モンクレールダウン[/url] [url=http://www.jacketsgukijp.com/]モンクレールジャケット[/url] [url=http://www.jacketsgukijp.com/]モンクレール激安[/url] [url=http://www.shoeonsalejp.com/]ナイキ シューズ[/url] [url=http://www.shoeonsalejp.com/]ナイキ ショックス[/url] [url=http://www.shoeonsalejp.com/]ナイキ 販売[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウバッグ[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウショルダーバッグ[/url] [url=http://www.miumiusuzujp.com/]ミュウミュウアウトレット[/url]')

BACKTRACE

FILE: (not given by php)
LINE: (not given by php)
CALL: msg_handler()

FILE: [ROOT]/includes/db/dbal.php
LINE: 754
CALL: trigger_error()

FILE: [ROOT]/includes/db/mysql.php
LINE: 175
CALL: dbal->sql_error()

FILE: [ROOT]/includes/auth/auth_db.php
LINE: 101
CALL: dbal_mysql->sql_query()

FILE: [ROOT]/includes/auth.php
LINE: 919
CALL: login_db()

FILE: [ROOT]/includes/functions.php
LINE: 3074
CALL: auth->login()

FILE: [ROOT]/ucp.php
LINE: 81
CALL: login_box()