>>If the WSH was an option, that's the way I'd go.
>
>Anyone has an exemple about that? I don't use that much and wouldn't be sure on the proper approach for that.

Something like this

oFSO = CREATEOBJECT("Scripting.FileSystemObject")
* lcfolder is the fully qualified 
* directory name
oFolder = oFSO.GetFolder(lcfolder)
FOR EACH oFile IN oFolder.Files
  oFile.Name = FORCEEXT(JUSTSTEM(oFile.Name) + TTOC(oFile.DateLastModified), JUSTEXT(oFile.Name)) 
NEXT

if I understand correctly.