Advanced Search (Activity AND Relationship) fails with "Not unique table/alias: 'contact_b'"

Discovered while testing v3.4.alpha1, but verified that it also affects v3.3.5: Advanced search on both Activity and Relationship in the same search fails with "Not unique table/alias: 'contact_b'". Commented error details (with offending file, line number) below:

[debug_info] =>
SELECT DISTINCT UPPER(LEFT(contact_a.sort_name, 1)) as sort_name
FROM civicrm_contact contact_a
LEFT JOIN civicrm_address ON ( contact_a.id = civicrm_address.contact_id AND civicrm_address.is_primary = 1 )
LEFT JOIN civicrm_state_province ON civicrm_address.state_province_id = civicrm_state_province.id
LEFT JOIN civicrm_country ON civicrm_address.country_id = civicrm_country.id
LEFT JOIN civicrm_activity_target ON civicrm_activity_target.target_contact_id = contact_a.id
LEFT JOIN civicrm_activity ON ( civicrm_activity.id = civicrm_activity_target.activity_id
AND civicrm_activity.is_deleted = 0 AND civicrm_activity.is_current_revision = 1 )

– CRM/Activity/BAO/Query.php line 384
LEFT JOIN civicrm_contact contact_b ON civicrm_activity.source_contact_id = contact_b.id
LEFT JOIN civicrm_email email_b ON (contact_b.id = email_b.contact_id AND email_b.is_primary = 1)

– CRM/Contact/BAO/Query.php line 2100
LEFT JOIN civicrm_relationship ON (civicrm_relationship.contact_id_a = contact_a.id )
LEFT JOIN civicrm_contact contact_b ON (civicrm_relationship.contact_id_b = contact_b.id )

WHERE ( civicrm_state_province.id IN (1037) AND civicrm_country.id = 1228 AND contact_b.is_deleted = 0 AND contact_b.sort_name LIKE '%%' AND civicrm_activity.source_contact_id = contact_b.id AND civicrm_activity.status_id IN (1,2) AND civicrm_relationship.is_active = 1 AND ( civicrm_relationship.end_date is NULL OR civicrm_relationship.end_date >= 20110225 ) AND civicrm_relationship.relationship_type_id = 17 ) AND (contact_a.is_deleted = 0)
[nativecode=1066 ** Not unique table/alias: 'contact_b']