Scheduled job 'process_pledge' which calls CRM_Pledge_BAO_Pledge::updatePledgeStatus is not processing overdue pledge payments

CRM_Pledge_BAO_Pledge::updatePledgeStatus is supposed to updated pledge statuses and pledge payment statuses based on reviewing payment due dates. It should also be sending a reminder for due / overdue pledge payments when reminder is configured for the pledge. Neither of these seem to be working.

Steps to recreate:
1. Create new pledge for a contact with pledge start date of Jan 1 2012 and Payment Start Date also Jan 1. Accept defaults for reminders.

• pledge status is overdue and pledge payment for Jan 1 is overdue
  2. Go to Scheduled Jobs and run process_pledge (Process Pledges) job.
• job lob shows "Success" and "0 records processed"
• no email reminder is sent

I also experimented with setting the Pledge status to Pending (status_id = 2) via phpMyAdmin to see if the function would update pledge status to Overdue. It does not.