cbtransfer crashes on 32-bit Linux with couchstore-files as a source

Steps to reproduce:
1. Create default bucket and load 100k items.
2. Run below command
sudo /opt/couchbase/bin/cbtransfer -v -v -v couchstore-files:///opt/couchbase/var/lib/couchbase/data/ /tmp/backup

ubuntu@ip-10-128-247-201:~$ sudo /opt/couchbase/bin/cbtransfer -v -v -v couchstore-files:///opt/couchbase/var/lib/couchbase/data/ /tmp/backup
2013-03-07 12:36:09,485: mt cbtransfer...
2013-03-07 12:36:09,486: mt source : couchstore-files:///opt/couchbase/var/lib/couchbase/data/
2013-03-07 12:36:09,486: mt sink : /tmp/backup
2013-03-07 12:36:09,486: mt opts : {'username': None, 'source_vbucket_state': 'active', 'destination_vbucket_state': 'active', 'verbose': 3, 'dry_run': False, 'extra':

{'max_retry': 10.0, 'rehash': 0.0, 'nmv_retry': 1.0, 'cbb_max_mb': 100000.0, 'try_xwm': 1.0, 'batch_max_bytes': 400000.0, 'report_full': 2000.0, 'batch_max_size': 1000.0, 'report': 5.0, 'recv_min_bytes': 4096.0}

, 'single_node': False, 'bucket_destination': None, 'destination_operation': None, 'threads': 4, 'key': None, 'password': None, 'id': None, 'bucket_source': None}
2013-03-07 12:36:09,486: mt source_class: <class 'pump_sfd.SFDSource'>
2013-03-07 12:36:09,649: mt sink_class: <class 'pump_bfd.BFDSink'>
2013-03-07 12:36:09,650: mt source_buckets: default
2013-03-07 12:36:09,650: mt bucket: default
2013-03-07 12:36:09,650: mt source_nodes: N/A
2013-03-07 12:36:09,651: mt enqueueing node: N/A
2013-03-07 12:36:09,651: w0 node: N/A
Segmentation fault (core dumped)