DbUpdateConcurrencyException not raised Database First - entity-framework

Question

I am currently following this tutorial for Concurrency Handling.
http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/handling-concurrency-with-the-entity-framework-in-an-asp-net-mvc-application
However, the DbUpdateConcurrencyException is not raised in my case. I'm using Database first approach in EF 5.0
I have Carrier object with 0..1 relationship with Address & Contact objects.
I have created the a RowVersion field in the Carrier table .
My code is as follows:
public Carrier UpdateCarrier(Carrier carrier)
{
try
{
var entry = ariesConfigContext.Entry<Carrier>(carrier);
if(entry.State == System.Data.EntityState.Detached)
{
var attachedEntity = ariesConfigContext.Carriers.Include(con => con.Contact).Include(a => a.Address).Single(c => c.CarrierID == carrier.CarrierID);
if(attachedEntity != null)
{
var attachedEntry = ariesConfigContext.Entry(attachedEntity);
attachedEntry.CurrentValues.SetValues(carrier);
attachedEntity.Contact = carrier.Contact;
attachedEntity.Address = carrier.Address;
}
else
{
entry.State = System.Data.EntityState.Modified;
}
}
ariesConfigContext.SaveChanges();
}
catch(DbUpdateConcurrencyException ex)
{
//do something
}
return carrier;
}
My Model is as follows:
namespace Aries.Domain.Models.AriesConfigDB
{
using System;
using System.Collections.Generic;
public partial class Carrier
{
public Carrier()
{
this.UserProfiles = new HashSet<UserProfile>();
}
public int CarrierID { get; set; }
public string Name { get; set; }
public string Abbreviation { get; set; }
public string Phone { get; set; }
public string Email { get; set; }
public string Memo { get; set; }
public string DBServerName { get; set; }
public string DBName { get; set; }
public string DBUser { get; set; }
public string DBPassword { get; set; }
public Nullable<int> AddressID { get; set; }
public Nullable<int> ContactID { get; set; }
public bool IsDeleted { get; set; }
public byte[] RowVersion { get; set; }
public virtual Address Address { get; set; }
public virtual Contact Contact { get; set; }
public virtual ICollection<UserProfile> UserProfiles { get; set; }
}
}
My View is:
#model Aries.Domain.Models.AriesConfigDB.Carrier
<div>
<div class="message-error">
#if (TempData["ErrorMessage"] != null)
{
<p>#TempData["ErrorMessage"]</p>
}
</div>
#Html.HiddenFor(model => model.CarrierID)
#Html.HiddenFor(model => model.RowVersion)
<div class="editor-label">
#Html.LabelFor(model => model.Name)
</div>
<div class="editor-field">
#Html.EditorFor(model => model.Name)
#Html.ValidationMessageFor(model => model.Name)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.Abbreviation)
</div>
....
....
I'm unable to get the Exception to be raised. Any help is appreciated.
UPDATE:
I already have a Metadata class for Carrier as below and I've added the [Timestamp] attribute there.
public class CarrierMetadata
{
public int CarrierID { get; set; }
[Required]
[MaxLength(255, ErrorMessage = "Carrier Name must be 255 characters or less")]
[Display(Name = "Carrier Name")]
public string Name { get; set; }
....
....
[Required]
[ConcurrencyCheck]
[Timestamp]
public byte[] RowVersion { get; set; }
}
And my Carrier class has the following attribute:
[MetadataType(typeof(CarrierMetadata))]
public partial class Carrier
{
}
But it still doesn't work.