"Required Attributes" are ignored when "Dynamic Required Attributes" are updated

I want to change the requirement of some attributes based on the value set on another attribute.
So I used 'Dynamic Required Attribute' operation behavior.
However, I then found that the Required Attributes are ignored (change to option) after modifying the value of the attribute in the Dynamic Required Attributes.
Is this expected?
Is this a bug?

References:
https://jazz.net/wiki/bin/view/Main/AttributeCustomization
jazz.net work item 174570

Steps to reproduce:
1. Create a new project area from Scrum Template
2. Assign yourself with appropriate process role
3. Follow the steps in the InfoCenter to implement Dynamic Required Attribute
https://jazz.net/help-dev/clm/index.jsp?topic=%2Fcom.ibm.team.workitem.doc%2Ftopics%2Ft_configuring_dynamic_required_attributes.html
4. Ensure you have some 'required attributes' defined.
5. Create a new work item. Confirm that the required attributes are displayed as mandatory
6. Change the value of the attribute that you used in your java script file (implemented in step#3). Notice that the required attributes are no longer mandatory.