Incomplete database schema, module is not working

Hi, I Just installed the module to test and realized I can't create codes.

Go to admin/user/regcodes/create

create a code with:
- code : test
- category : test

and the following error appears:

user warning: Unknown column 'is_onetime' in 'field list' query: INSERT INTO regcode (created,begins,expires,category,code,is_active,is_onetime) VALUES (NOW(), NULL, NULL, "test", "test", 1, 0) in E:\xampplite\htdocs\drupal6\sites\all\modules\contributions\modules\regcode\regcode.api.php on line 120.

Reviewed the .install file, and the schema has no any field named "is_onetime".

I would provide the patch, but I don't know if is_onetime is a feature for this version or not. The api supports this, but the create code interface has no option to mark as "one time code", instead it has a field named "maxuses" that is not populated in the API.

Note: marked as critical, the module doesn't work