probably is a problem with inflector_helper. I would recommend you to explicitly set $table and $name in your model class. Maybe it's an error in the relations ($has_one and $has_many properties). Another tip to keep in count is that you must name relationships using model names alphabetically ordered.
Please provide more code.
PS: I'm Spanish, so send me a PM in order to try to help you and then we'll update this entry to register the right solution.