Just an FYI. The preferred way to create an object is like so

```ruby
interface = service.interfaces.new(:vnet => 'dsfadf', :model => 'dafdfds')
```
This should automatically merge everything into the attributes hash. 

If do do want to create Interfaces using regular ruby syntax you will need to pass in a key of `:service` and the value of the service object in order to support `save`, `destroy`, and `reload` operations.