patch to disable the transactional logic during the cleaning of the DB, this
fixes a problem seen as result of updates of BerkeleyDB.
See http://bugs.debian.org/614968 for more info

--- a/postgrey
+++ b/postgrey
@@ -276,11 +276,7 @@
                 $nr_keys_after++;
             }
         }
-        my $db_obj = $self->{postgrey}{db_obj};
-        my $txn = $db_env->txn_begin();
-        $db_obj->Txn($txn);
         for my $key (@old_keys) { delete $db->{$key}; }
-        $txn->txn_commit();
         
         $self->mylog(1, "cleaning main database finished. before: $nr_keys_before, after: $nr_keys_after");
 
@@ -300,11 +296,7 @@
                     $nr_keys_after++;
                 }
             }
-            my $db_cawl_obj = $self->{postgrey}{db_cawl_obj};
-            $txn = $db_env->txn_begin();
-            $db_cawl_obj->Txn($txn);
             for my $key (@old_keys_cawl) { delete $cawl_db->{$key}; }
-            $txn->txn_commit();
 
             $self->mylog(1, "cleaning clients database finished. before: $nr_keys_before, after: $nr_keys_after");
         }