Cannot record contributions in a data entry batch of type pledge payment

Per the improvement described at: https://issues.civicrm.org/jira/browse/CRM-15701
(which worked in a previous version of 4.6.x)

This is not working properly in version 4.6.3. Specifically when I try to record stand-alone contributions in a "pledge payment" type data entry batch which also includes pledge payments, I get an error and cannot validate my batch.

The error message I get is:
Please correct the following errors in the form fields below:
You can not record two payments for the same pledge in a single batch

To reproduce the issue:
1) create a new data entry batch of type "pledge payment"

2) add some rows with pledge payments

3) Add at least one row with no pledge selected. (ie a stand-alone contribution)

4) Click the button "Validate and process the batch"