Fix assumption that the time test is always in -0800

If you're (un?)fortunate enough not to live in California, the tests fails:

<pre>
# Running tests:

..............................................expected:
<root>2011-11-16T13:36:08-08:00</root>

got:
<root>2011-11-16T21:36:08+00:00</root>
</pre>