Opteka is currently developing five new lenses for various mirrorless systems including Micro Four Thirds. This is their official press text:
Five new Opteka mirrorless lenses are currently in production. Each lens will be available in Sony E-mount, Fuji X-mount, Olympus and Panasonic Micro Four Thirds, Canon EOS-M mount, and Nikon CX mount. 43rumors
Further details will be provided after our final micron-level quality control checks have been completed.