Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/ayatanawebmail/application.py", line 182, in __init__
    gi.require_version('AyatanaAppIndicator3', '0.1')
  File "/usr/lib/python3/dist-packages/gi/__init__.py", line 126, in require_version
    raise ValueError('Namespace %s not available' % namespace)
ValueError: Namespace AyatanaAppIndicator3 not available

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/bin/ayatana-webmail", line 31, in <module>
    AyatanaWebmail((len(sys.argv) == 2 and sys.argv[1] == 'debug') or m_bDebug)
  File "/usr/lib/python3/dist-packages/ayatanawebmail/application.py", line 502, in __init__
    self.oMessagingMenu = MessagingMenu(self.onMenuItemClicked, self.openDialog, self.updateMessageAges, self.fnCheckNetwork)
  File "/usr/lib/python3/dist-packages/ayatanawebmail/application.py", line 187, in __init__
    gi.require_version('AppIndicator3', '0.1')
  File "/usr/lib/python3/dist-packages/gi/__init__.py", line 126, in require_version
    raise ValueError('Namespace %s not available' % namespace)
ValueError: Namespace AppIndicator3 not available