Wrong results when applying the <= operator to a string attribute having a null token defined

The query having("myField").lte("Something") gets translated to lucene as myField:['_null_' TO 'Something'] where null is the defined null token for this field. This query returns wrong results or no results at all, depending on the value of the null token. The issue no longer appears if there is no null token defined; it will get properly translated to myField:[* TO 'Something'] .