Flagging Field issue - non default value issue

This issue was raised from: https://support.atlassian.com/browse/GHS-580

Steps to replicate the problem:

• Create a Multi Select and Multi Checkbox custom fields via Administration > Issue Fields > Custom Fields. Ensure the custom field is configured with a value.
• Set the field as flagging field via GreenHopper tab > Planning Board > Configuration > Add the custom field as the flagging field
• In the Planning Board, flag an issue
• Edit the issue by changing the flagging value
• After changing the flagging value, close the popup

The issue is no longer being flagged.