Actually, I meant the CZ 135/1.8. Photozone.de has reviews for both APS-C and FF, have a look... both of them end with the same phrase: 'The entry hurdle for the Zeiss ZA T* 135mm f/1.8 is quite high at around 1300EUR/US$
but if you want the very best this is the one. Highly recommended! '
Personally, I would go for the 135STF (a unique lens, across all makers) over the CZ, but I doubt you will find a better autofocus lens (135mm prime, that is) than the CZ.
There is also a CZ85/1.4 with AF available in A-mount indeed (but bear in mind that it's a whole different design from the manual-focus Planar T), some prefer it for its sharpness and microcontrast, I would choose the Minolta version because it has slightly better bokeh, and an overall different (more pleasing, to me) rendition. I had the 85G actually, before moving to Pentax. Now I'm glad to report that the FA77 does very well in keeping up with that lens (while not quite matching it, I'm afraid), at a fraction of its weight and size
As for converting one of the a-mount Zeiss lenses, Blue is (partially) right, there is no point in doing that, as you would lose the advantage they have over any other CZ lenses: autofocus.
The STF... now that's another story, because it's a manual focus lens anyway. If only I could find someone able to convert it to K-mount
EDIT - I just checked the CZ website, unless they once had a discontinued model (not listed there anymore), it seems that they don't even make a 135/1.8 for any other mounts except Sony/Minolta
AND A LATER EDIT for those that will bother to read the reviews of ZA lenses - Photozone will mention a little play in the focusing ring as a 'nitpick' - it's not a QC issue, that's a design aspect, all ZA lenses have it (don't ask me why, though)