Maybe with the consent of Ricoh, the PF has done this:
http://www.pentaxforums.com/articles/pentax-news/pentax-full-frame-officially-coming-cpplus-2015.html
Do note that the PENTAX logo is a sticker, though. :o :(
So, after waiting for more than ten years, the Pentax 135 K-mount should come this fall, finally.
Related:
My Pentax Lenses are Given Completely New Lives! :-D
This is What the Limited Lenses Should be Put Onto!
DIY: Adapting the Pentax FA*85/1.4 onto the Cantax K-5D Mark III
Compatibility of DA Lenses on Full Frame