object.CreateFolder(foldername)

var fso = new ActiveXObject("Scripting.FileSystemObject");
var a = fso.CreateFolder("c:\\new folder");

Function CreateFolderDemo
   Dim fso, f
   Set fso = CreateObject("Scripting.FileSystemObject")
   Set f = fso.CreateFolder("c:\New Folder")
   CreateFolderDemo = f.Path
End Function