When Using Batch Update via Profile, custom Display name and Sort name is Reset to Default

The demo site has a non-recoverable error when taking step 1, (Thread stack overrun).

To replicate:
1. Create a custom format for sort name and display name
2. search for contacts
3. use batch update via profile to update contacts
4. notice how display name and sort name are reset to the default, and the custom format is ignored
5. if you edit each contact, the correct custom display name and sort name are restored