RC-0: Can't resolve parameter --> param: { new (): T; }

I’m facing a problem with metadata_resolver.js

metadata_resolver.js:499Uncaught Error: Can't resolve all parameters for HttpService: (Http, String, String, ?)

I have this generic provider that receives as parameter a Class, so in run time it could create an object or call a static method of this class.
Both providers are in providers array in app.module.ts

@Injectable()
export class ClassAService extends HttpService<ClassA> {

	constructor(http: Http) {
		super(http, 'baseUrl', "endpoint", ClassA);
	}

@Injectable()
export class HttpService<T> {

	private _collection$: Subject<T[]>;
	private _baseUrl: string;
	private _dataStore: {
		collection: any[]
	};
	private _constructor: any;
	private _endpoint: String;

	constructor(public http: Http, private baseUrl: string, endpoint: string, constructor: { new (): T; }) {
        ...
        }

        loadAll(): void {

	     this.http.get(`${this._baseUrl}/${this._endpoint}`)
		.map(response => response.json())
		.subscribe(
			data => {
				this._dataStore.collection = <T[]>this._constructor.fromJSONArray(this._constructor, data);
				this._collection$.next(this._dataStore.collection);
			},
			error => console.log(error),
			() => console.log('done')
		);
        }
}
}

myComponent.ts

import { ClassAService } from '../../providers/classA-service';
import { ClassA } from '../../models/classA';


export class MyComponent {

  list_a: ClassA[];

  constructor(public _dataservice: ClassAService, public viewCtrl: ViewController) {

    this._dataservice.collection$.subscribe(
      collections => { this.list_a = collections; console.log(this.list_a); });

    this._dataservice.loadAll();

  }

}

So, it was an injection problem because of both providers was in providers array of app.module.ts