[Вопрос к АДМИНИСТРАЦИИ форума]Новая тема

В "компьютеры и средства связи" (здесь как видите создалось нормально) при попытке создать новую тему выдает третий день:
Общая ошибка
SQL ERROR [ mysqli ]
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1 [1064]
SQL
SELECT t.topic_title as topic_title, '' as username FROM main_topics as t WHERE (t.topic_id=)
BACKTRACE
FILE: includes/db/mysqli.php
LINE: 143
CALL: dbal->sql_error()
FILE: includes/functions_content.php
LINE: 522
CALL: dbal_mysqli->sql_query()
FILE: includes/functions_content.php
LINE: 618
CALL: search_topic_title()
FILE: includes/functions_content.php(705) : regexp code
LINE: 2
CALL: make_clickable_callback()
FILE: includes/functions_content.php
LINE: 705
CALL: preg_replace()
FILE: includes/message_parser.php
LINE: 1240
CALL: make_clickable()
FILE: includes/message_parser.php
LINE: 1137
CALL: parse_message->magic_url()
FILE: posting.php
LINE: 710
CALL: parse_message->parse()
Общая ошибка
SQL ERROR [ mysqli ]
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1 [1064]
SQL
SELECT t.topic_title as topic_title, '' as username FROM main_topics as t WHERE (t.topic_id=)
BACKTRACE
FILE: includes/db/mysqli.php
LINE: 143
CALL: dbal->sql_error()
FILE: includes/functions_content.php
LINE: 522
CALL: dbal_mysqli->sql_query()
FILE: includes/functions_content.php
LINE: 618
CALL: search_topic_title()
FILE: includes/functions_content.php(705) : regexp code
LINE: 2
CALL: make_clickable_callback()
FILE: includes/functions_content.php
LINE: 705
CALL: preg_replace()
FILE: includes/message_parser.php
LINE: 1240
CALL: make_clickable()
FILE: includes/message_parser.php
LINE: 1137
CALL: parse_message->magic_url()
FILE: posting.php
LINE: 710
CALL: parse_message->parse()