Default PatternLayout date format is not ISO8601

[Eric Chamberlain <ec...@ventripoint.com>]

I could find no FAQ on this so I am reporting this here.  Everyone repeats that
%date{ISO8601} will produce ISO8601 format for dates.  Beyond that, the documentation says
that the default form of the %date in PatternLayout is ISO8601.

This appears to be wrong based on the statement of the ISO8601 standard at
http://www.w3.org/TR/NOTE-datetime.  

An example should illustrate the difference easily.

Sample output of %date{ISO8601}:

2008-06-27 15:24:27,421

But if the above elements (down to the fractional second) are to be displayed, the ISO8601
standard says it should be (assuming Pacific Time in this sample)

2008-06-27T15:24:27.421-07:00

The ISO8601 correct format is *possible* in log4net, of course, but it is not the default.
I don't know whether this is a bug in log4net or whether the documentation is just out of
date or what.  I will leave that for others to sort out but there is a mismatch between
the documentation and the behavior.

Eric Chamberlain
VentriPoint, Inc. | www.ventripoint.com | Software Engineer 
Helping heart care through innovative diagnostic solutions