I'd like to know how to do that, someone send me this information. But I can't find these plug ins
Saving documents for use with InDesign 2.0
You can export InDesign CS documents in InDesign Interchange format (.INX) for compatibility with InDesign 2.0. To open these documents in version 2.0, you'll need to obtain and install the Scripting plug-in and the XML Reader plug-in. You can obtain these plug-ins from the Adobe Web site.
Saving documents for use with InDesign 2.0
You can export InDesign CS documents in InDesign Interchange format (.INX) for compatibility with InDesign 2.0. To open these documents in version 2.0, you'll need to obtain and install the Scripting plug-in and the XML Reader plug-in. You can obtain these plug-ins from the Adobe Web site.