Custom Alert Channel in SharePoint Portal Server 2003

Visitors to Microsoft Office SharePoint Portal Server portal or team sites surely are aware of the Alert Me link. You can get notified when content within one of the sites is created, updated, or deleted. To get the alert results, a user must create an alert. Out of the box, Microsoft Office SharePoint Portal Server 2003 is able to notify a user either through the portal site or through an e-mail message. We would like to give the user the opertunity to be notified through MSN. So when the user chooses an Alert he can by defualt add his Email Address. We would like to have an option next to it with the Option "Alert me throug MSN". There is already an Articel with code under MSDN [login to view URL] We would like to add the option "send alerts to my Windows Messenger Account" So the User must be notified by MSN Service, that for example an new Document, or Announcements has be added. When he received the Alert through Messenger clicking on it redirects him to the Sharepoint URL.