<p>Just to resurrect this thread... They did make an OM-mount Ultron 40mm f/2. I have one, new-in-box. (For sale if anyone really has to have it.) </p>
<p><img src="http://edsawyer.com/lens/OM_gear/voigtlander_ultron_40mm_f2/IMG_5948.JPG" alt="" width="600" /></p>