We thought we discovered something great when we started using the ActiveXObject('Sharepoint.OpenDocuments.1') approach recently to open Office docs with full Sharepoint 2001 check-out/Document Management support from within IE.
var objDoc = new ActiveXObject('Sharepoint.OpenDocuments.1');
The code is an excerpt from the updated FolderItemsPart.xsl webpart available from MS here.
Then we started upgrading workstations from W2K3 Professional to Windows XP Professional and it stopped working! The webpart doesn't work either.
We turned off “browse in same window“ in Folder-->Folder Options-->Filetypes-->Advanced. That opened in native Word alright, but we lost the ability to check-out or do any SPS functions with the doc. We updated the Microsoft Windows Script located here, we registered \windows\system32\scrrun.dll. We reinstalled the SPS 2003 Client Components found here. Nothin'.
We could direct people to the folder containing the doc, then the user could open the doc with full Sharepoint DM support, but oh, darn, if the URL is longer than 100 characters, the folder won't OPEN in a window. (That beef is located here.)