The check for DB_RECNO seems to do the opposite of what it's supposed to do:

    def append(self, value, txn=None):
        if self.get_type() != db.DB_RECNO:
            self.append = self.__append
            return self.append(value, txn=txn)
        raise db.DBError, "append() only supported when dbshelve opened
with filetype=dbshelve.db.DB_RECNO"

Gregory, could you take a look at this?

heh yep that does look like a bug.  Laughing at that one goes well with
this comment currently in test_dbshelve.py:

# TODO:  Add test cases for a DBShelf in a RECNO DB.

i'll fix it. :)

Fixed in python trunk r58434, release25-maint r58435, py3k r58438