[SQLObject] autoCommit=False and Transaction -> SQLObjectNotFound on creation

Hello,

Problem: 

$ dropdb scratch; createdb scratch; python /tmp/scratch.py 
Traceback (most recent call last):
  File "/tmp/scratch.py", line 25, in <module>
    er = Eingangsrechnung(name="test")
  File
 "/home/gregor/work/gnucash/testve/local/lib/python2.7/site-packages/sqlobject/main.py",
line 1226, in __init__
    self._create(id, **kw)
  File
 "/home/gregor/work/gnucash/testve/local/lib/python2.7/site-packages/sqlobject/main.py",
line 1274, in _create
    self._SO_finishCreate(id)
  File
 "/home/gregor/work/gnucash/testve/local/lib/python2.7/site-packages/sqlobject/main.py",
line 1301, in _SO_finishCreate
    self._init(id)
  File
 "/home/gregor/work/gnucash/testve/local/lib/python2.7/site-packages/sqlobject/main.py",
line 934, in _init
    raise SQLObjectNotFound, "The object %s by the ID %s does not
 exist" % (self.__class__.__name__, self.id)
sqlobject.main.SQLObjectNotFound: The object Eingangsrechnung by the ID
1 does not exist

--------------------

$ cat /tmp/scratch.py 
from sqlobject import SQLObject, sqlhub, connectionForURI, ForeignKey,
StringCol

sqlhub.processConnection =
connectionForURI('postgres://gregor@localhost/scratch?debug=0&autoCommit=1')

class Person(SQLObject):
     name = StringCol()

class Eingangsrechnung(SQLObject):
     name = StringCol()

class Buchung(SQLObject): 
     eingangsrechnung = ForeignKey('Eingangsrechnung')
     person = ForeignKey('Person')


Person.createTable()
Eingangsrechnung.createTable()
Buchung.createTable()

sqlhub.processConnection.autoCommit = False
t = Person._connection.transaction()
er = Eingangsrechnung(name="test")
pr = Person(name="test")
Buchung(person=pr, eingangsrechnung=er)
t.commit()

----

It works if I remove the transaction lines, or set autoCommit =True. 
I have tested this with SQLObject 0.12.4 and 2.0.0, same behaviour.
Is this a bug, or do I do something wrong?

--
Greg