hey guys im having a issue with my assembly files and get the error  'businesslogic' does not exist in namespace 'umbraco.cms' when i try to combile the project. I have made sure i have included cms.dll, businesslogic.dll and umbraco.dll in the bin folder.

Im trying tro replicate what blog4umbraco is doing with the autopopulate postDate. Below is the code, any idea where im going wrong? thanks

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using umbraco;
using umbraco.BusinessLogic;
using umbraco.BusinessLogic.console;
using umbraco.cms.businesslogic.web;

namespace UmbracoCmsNews
{
    public class NewsCms : umbraco.BusinessLogic.ApplicationBase 
    {

        void Document_New(Document sender, umbraco.cms.businesslogic.NewEventArgs e)
        {

            if (sender.ContentType.Alias == "News_Article_doc")
            {

                if (sender.getProperty("postDate") != null)
                {

                    sender.getProperty("postDate").Value = sender.CreateDateTime.Date;

                }

            }

        }
    }
}