Cannot modify header information

I recently upgraded to R2 from R2RC3. I welcome suggestions regarding the following error:

1. URL: http://ipolity.com/events/edit.php
2. REFERRER: http://ipolity.com/events/edit.php?events_id=2
3. HOST: ipolity.com
4. IP: 72.184.109.238
5. SQL: INSERT INTO `liberty_content_history` ( `content_id`, `version`, `last_modified`, `user_id`, `ip`, `data`, `summary`, `history_comment`, `format_guid` ) VALUES ( '995', '1', '1194211641', '2', '72.184.109.238', 'this is just a test', NULL, '', 'tikiwiki' )
6. ERROR CODE: Errno: 1062 Message: Duplicate entry '0-1' for key 1

}}}}}}}}}}} -> bit_error_string(Array6)
}}}}}}}}}}} LINE: 638, /home/ipolity/public_html/kernel/BitDbAdodb.php
}}}}}}}}}} -> bit_error_handler(mysql, bit_error_handler, 1062, Duplicate entry '0-1' for key 1, INSERT INTO `liberty_content_history` ( `content_id`, `version`,..., false, Object:ADODB_mysql)
}}}}}}}}}} LINE: 226, /home/ipolity/public_html/util/adodb/adodb.inc.php
}}}}}}}}} -> ADODB_TransMonitor(mysql, EXECUTE, 1062, Duplicate entry '0-1' for key 1, INSERT INTO `liberty_content_history` ( `content_id`, `version`,..., false, Object:ADODB_mysql)
}}}}}}}}} LINE: 916, /home/ipolity/public_html/util/adodb/adodb.inc.php
}}}}}}}} -> ADOConnection::_Execute(INSERT INTO `liberty_content_history` ( `content_id`, `version`,...)
}}}}}}}} LINE: 872, /home/ipolity/public_html/util/adodb/adodb.inc.php
}}}}}}} -> ADOConnectionExecute(INSERT INTO `liberty_content_history` ( `content_id`, `version`,..., Array9)
}}}}}}} LINE: 247, /home/ipolity/public_html/kernel/BitDbAdodb.php
}}}}}} -> ADOConnectionBitDbAdodb::query(INSERT INTO `liberty_content_history` ( `content_id`, `version`,..., Array9)
}}}}}} LINE: 475, /home/ipolity/public_html/kernel/BitDbBase.php
}}}}} -> ADOConnectionBitDbAdodbassociateInsert(liberty_content_history, Array9)
}}}}} LINE: 478, /home/ipolity/public_html/liberty/LibertyContent.php
}}}} -> ADOConnectionBitDbAdodbLibertyContent::storeHistory()
}}}} LINE: 336, /home/ipolity/public_html/liberty/LibertyContent.php
}}} -> ADOConnectionBitDbAdodbLibertyContentstore(Array35)
}}} LINE: 306, /home/ipolity/public_html/liberty/LibertyAttachable.php
}} -> ADOConnectionBitDbAdodbLibertyContentLibertyAttachable::store(Array35)
}} LINE: 140, /home/ipolity/public_html/events/BitEvents.php
} -> ADOConnectionBitDbAdodbLibertyContentLibertyAttachablestore(Array35)
} LINE: 53, /home/ipolity/public_html/events/edit.php


$_POST:
array (
'tk' => 'dd7d00404bc98956c4d9',
'events_id' => '2',
'events_date' => '',
'title' => 'test event',
'description' => 'testing',
'cost' => '',
'event_time' => '',
'end_time' =>
array (
'Hour' => '04',
'Minute' => '45',
'Meridian' => 'pm',
),
'format_guid' => 'tikiwiki',
'edit' => 'this is just a test

test',
'tags' => '',
'security_id' => 'public',
'security_description' => '',
'access_question' => 'What is the password to view this Event?',
'access_answer' => '',
'save_events' => 'Save',
)

$_COOKIE:
array (
'tz_offset' => '-18000',
'phpbb2mysql_data' => 'a:2:{s:11:\\"autologinid\\";s:32:\\"84c6c0c2f8d048cb1a7d31963f45bba0\\";s:6:\\"userid\\";s:1:\\"2\\";}',
'BWSESSION' => '3a3e235fc9067c9487cc3f14d5802308',
'bit-user-ipolity' => '3a3e235fc9067c9487cc3f14d5802308',
'javascript_enabled' => 'y',
'webfxtab_' => '0',
)

$_FILES:
array (
'upload' =>
array (
'name' => '',
'type' => '',
'tmp_name' => '',
'error' => 4,
'size' => 0,
),
)

Warning: Cannot modify header information - headers already sent by (output started at /home/ipolity/public_html/kernel/bit_error_inc.php:41) in /home/ipolity/public_html/events/edit.php on line 54

This particular error was due to duplicate database information created in liberty_content when improperly upgrading to R2. Once duplicate information was deleted, functionality returned to normal.