Organization import skips rows with duplicate emails ignoring duplicate match settings

CiviCRM 1.8.beta.10676 / Drupal 5.2, also reproduced on demo.civicrm.org CiviCRM 10569.

I initially found this problem when importing using a relationship from organization to individual, but have reproduced with a very simple import involving organizations only. I report the simple case here; if resolving this does not fix the relationship import, I'll report that separately.

Steps to reproduce - Case A:
---------------------------------------
Import the attached file test-import-org.csv with the following settings:

• Matching Rules for Organization Contacts: no matching (e.g. total = 100 or no fields selected)
  Import Step 1:
• First row contains column headers
• Contact Type: Organization
• For Duplicate Contacts: No Duplicate Checking
• Any date format
  Import Step 2:
• Default field mapping (Org name, Email (Home))

Expected result - Case A:
----------------------------------
Both rows imported, 2 Orgs created.

Actual result - Case A:
------------------------------
2nd row skipped: "CiviCRM has detected 1 records with conflicting email addresses within this data file. If you continue, these records will be skipped."

Steps to reproduce - Case B:
---------------------------------------
As Case A except:

• Matching Rules for Organization Contacts: Email only (Email 10, threshold 10)
• For Duplicate Contacts: Update

Expected result - Case B:
----------------------------------
Both rows imported, 1 Org created, Org name initially Testco East, updated to Testco West.

Actual result - Case B:
------------------------------
2nd row skipped: "CiviCRM has detected 1 records with conflicting email addresses within this data file. If you continue, these records will be skipped."