bindable property to extend the textbox

[Tommy]

I have subclassed the textbox and added a property to it with the following
code:

'--------------------------------------------------------
Imports System.ComponentModel
Public Class clsTextBox
Inherits System.Web.UI.WebControls.TextBox
Private _iPricePk As Integer
<Bindable(BindableSupport.Yes)> Public Property iPricePK() As Integer
Get
Return Me._iPricePk
End Get
Set(ByVal Value As Integer)
Me._iPricePk = Value
End Set
End Property
End Class
'--------------------------------------------------------

It shows up in the designer and acts like it's getting bound but when i
check the value of the property in my code it still has the default value.

Is there something else that needs to be done to make this actually bind?

Thanks