From time to time I can't access bugs.jquery.com. Page reload usually fixes the issue.

Here is a stack-trace from last failure (when I was trying to login):

Traceback (most recent call last):
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/api.py", line 436, in send_error
    data, 'text/html')
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/chrome.py", line 827, in render_template
    message = req.session.pop('chrome.%s.%d' % (type_, i))
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/api.py", line 212, in __getattr__
    value = self.callbacks[name](self)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/main.py", line 300, in _get_session
    return Session(self.env, req)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/session.py", line 199, in __init__
    self.promote_session(sid)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/session.py", line 258, in promote_session
    @self.env.with_transaction()
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/db/api.py", line 82, in transaction_wrapper
    ldb.rollback()
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/db/mysql_backend.py", line 264, in rollback
    self.cnx.ping()
OperationalError: (2006, 'MySQL server has gone away')