Mac OS X : lower_case_table_names and case-sensitive filesystem

Hello,

i've just updated my mysql database from 5.1 to mariadb 5.5.33a on macosx with a case-sensitive filesystem (via macports).

Now, i get foreign-key constraints errors, when truncate a table because the table-names doesn't match any longer.
lower_case_table_names is set to 0 and it is not possible to change it to another value.

Kind regards,
Klaus