Changing H3PO4 to H3PO3 without P4O6

[Char. Limit]

Is there any method, using common laboratory materials, to change phosphoric acid (H3PO4) to phosphorous acid (H3PO3)?

Assume that P4O6 is not available for purchase, but methods to make it are welcome.

This is for a culminating project, so not really homework, but I don't know where else to turn. Even my chemistry teacher doesn't know.

 

[Char. Limit]

Just another question:

If H3PO3 is a "reducing agent" and H3PO4 is a by-product of the reduction, can an opposite reaction be carried out to yield H3PO3?

 

[Char. Limit]

Does no one om this illustrious forum know?

 

[MATLABdude]

You can probably set up an electrochemical cell (using an appropriate oxidation half reaction) to convert the phosphate to phosphite:
http://en.wikipedia.org/wiki/Standard_electrode_potential_(data_page )

(It's about half-way down, search for po4)

EDIT: Or maybe drive the reaction using an electrolytic one.

 

[Char. Limit]

Excellent...

How should I do that, or should I ask my chemistry teacher?

2,718,282 thanks to you.