lens - Where can I get an extension tube for micro-four-thirds lenses?

There doesn't seem to be any extension tube set listed on the m4/3 section of the Four Thirds website. Olympus makes the EX-25 extension tube but it's for regular Four Thirds lenses.

I would like to do some macro photography, but the two lenses I have need the electronic contacts for aperture adjustment and image stabilization (can't live without the former, painful to get rid of the latter).