CSV-Import breaks

This Bug is against rev4889M.

The CSV-Import ist broken. I had got this problem with two totaly different CSV-Files.
Here is the Error-Log:

Array
(
[callback] => Array
(
[0] => CRM_Core_Error
[1] => handle
)

[code] => -19
[message] => DB Error: no such field
[mode] => 16
[debug_info] => UPDATE civicrm_location
SET is_primary = false WHERE
entity_table = 'civicrm_contact' AND
entity_id = '14' [nativecode=1054 ** Unknown column 'false' in 'field
list']
[type] => db_error
[user_info] => UPDATE civicrm_location
SET is_primary = false WHERE
entity_table = 'civicrm_contact' AND
entity_id = '14' [nativecode=1054 ** Unknown column 'false' in 'field
list']
[to_string] => [db_error: message="DB Error: no such field" code=-19
mode=callback callback=CRM_Core_Error::handle prefix="" info="UPDATE
civicrm_location
SET is_primary = false WHERE
entity_table = 'civicrm_contact' AND
entity_id = '14' [nativecode=1054 ** Unknown column 'false' in 'field
list']"]
)