http://weblogs.asp.net/jan/archive/2009/09/03/customizing-the-sharepoint-ecb-with-javascript-part-1.aspx
http://weblogs.asp.net/jan/archive/2009/09/04/customizing-the-sharepoint-ecb-with-javascript-part-2.aspx
http://weblogs.asp.net/jan/archive/2009/09/11/customizing-the-sharepoint-ecb-with-javascript-part-3.aspx