clipped from: forum.mflenses.com   
That sounds interesting.
I shot portraits with this lens one week ago and I was overwhelmed by the quality.

Here I found something about serial numbers beginning with 0

000xxxxxx factory test (study) models (prototypes etc) mod?les d'études
d'usine (prototypes etc..)
00xxxxxx preseries models reserved for members of the communist party
and "VIPs" (reservés aux membres du parti communist et haut
responsables en pré-série)
0xxxxxx reserved for factory syndicat leaders (réservés aux
responsables syndicaux d'usines)

http://forum.mflenses.com/a-word-about-russian-serial-numbers-t3332,highlight,serial.html