strange results from sys.version

[John Machin]

I am trying to help a user of my xlrd package who says he is getting 
anomalous results on his "work computer" but not on his "home computer".

Attempts to reproduce his alleged problem in a verifiable manner on his 
"work computer" have failed, so far ... the only meaning difference in 
script output is in sys.version

User (work): sys.version: 2.7 (r27:82500, Aug 23 2010, 17:18:21) etc
Me         : sys.version: 2.7 (r27:82525, Jul  4 2010, 09:01:59) etc

I have just now downloaded the Windows x86 msi from www.python.org and 
reinstalled it on another computer. It gives the same result as on my 
primary computer (above).

User result looks whacked: lower patch number, later date. 
www.python.org says "Python 2.7 was released on July 3rd, 2010."

Is it possible that the "work computer" is using an unofficial release? 
What other possibilities are there?

Thanks in advance ...