When I try to save a category translation I have the following errors:

* recoverable fatal error: Object of class stdClass could not be converted to string in D:\www\magnus\sites\all\modules\translatable\translatable.module on line 313.
* warning: mysql_real_escape_string() expects parameter 1 to be string, array given in D:\www\magnus\includes\database.mysql.inc on line 400.
* warning: mysql_real_escape_string() expects parameter 1 to be string, array given in D:\www\magnus\includes\database.mysql.inc on line 400.
* recoverable fatal error: Object of class stdClass could not be converted to string in D:\www\magnus\sites\all\modules\translatable\translatable.module on line 313.

My vocabulary permits tree-like hierarchy and related terms.