I noticed that our python library is generating the wrong time zone offset for ISO 8601 time stamps. Here is what I found:

$ python
Python 2.6.6 (r266:84292, Dec 7 2011, 20:48:22)
>>> import time
>>> print time.strftime("%z")
-0800
>>> print time.timezone
28800

so far, so good. However:

>>> print time.strftime("%z", time.localtime( int(time.time()) ))
+0000
>>> print time.strftime("%z",time.localtime())
+0000

This is wrong.

I believe that the time.localtime() function is not working properly. In C this would assemble the struct tm record, and strftime in C has no problems with the zone info. I am sure that python recommends to use some other way to get the proper time stamp assembled so that strftime() will be able to put a proper zone into it.