We would like to integrate Alfresco with a desktop environment running MSOffice 2002. We have had a look to the new Office 2003 Plugin Alfresco provides. Is Alfresco support Office 2002? we are ready to rewrite the code looking at the logic written for MS Office 2003
Alfresco currently has no plans to provide add-ins for MSOffice 2002.
If you want to undertake this, I suggest you grab the Office 2003 add-in source code to become familiar with it, also read up on Visual Studio Tools for Office. A good resource for the latter is the MSDN forum here: http://forums.microsoft.com/msdn/showforum.aspx?forumid=16&siteid=1
You should only need to change the Office application-specific code in a couple of classes in the add-in client (do a diff on Word and Excel to help see these). The web scripts are completely reusable, as are most of the configuration and authentication parts.
The source for the Office 2003 add-ins is in the projects/extensions folder. (Please note that the Office 2007 code is experimental and incomplete.)
By the way, the add-ins don't use web services at all. Authentication is done via a combination of querying an existing CIFS connection and/or HTTP authentication via the WebDAV interface. The user interface is entirely web script-based using an embedded MSIE control; with the exception of the initial configuration dialog.