Initenv for '/var/lib/trac/shipping_tracker' failed.
 Failed to create environment.
(1050, "Table 'system' already exists")
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/trac/admin/console.py", line 583, in do_initenv
    options=options)
  File "/usr/lib/python2.6/dist-packages/trac/env.py", line 207, in __init__
    self.create(options)
  File "/usr/lib/python2.6/dist-packages/trac/env.py", line 341, in create
    DatabaseManager(self).init_db()
  File "/usr/lib/python2.6/dist-packages/trac/db/api.py", line 86, in init_db
    connector.init_db(**args)
  File "/usr/lib/python2.6/dist-packages/trac/db/mysql_backend.py", line 98, in init_db
    cursor.execute(stmt)
  File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 166, in execute
    self.errorhandler(self, exc, value)
  File "/usr/lib/pymodules/python2.6/MySQLdb/connections.py", line 35, in defaulterrorhandler
    raise errorclass, errorvalue
OperationalError: (1050, "Table 'system' already exists")