AFIK you can use 700 tubes.... the 20mm difference in diameter or whatever it is is taken up by the stretchyness of the tube.
At the bottom of the page under tubes Sheldon suggests they are interchangeable...
http://www.sheldonbrown.com/harris/tires/630.html
@AngryPenguin started
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AFIK you can use 700 tubes.... the 20mm difference in diameter or whatever it is is taken up by the stretchyness of the tube.
At the bottom of the page under tubes Sheldon suggests they are interchangeable...
http://www.sheldonbrown.com/harris/tires/630.html