Defining Namespaces for a Group
To define namespaces for a group, follow these steps:
Click Groups in the left tree menu. A list of groups appears.
Click your target group.
Under the target group, click Namespaces.
Click the Add tab.
Enter a prefix for your namespace into the Prefix field.
Enter a URI for your namespace into the Namespace Uri field.
If you are defining a prefix for the universal unnamed namespace, leave the Namespace Uri field blank.
To add more namespace definitions, click More Items and repeat Step 5 - Step 6 for each namespace as needed.
Scroll to the top or bottom and click OK.
The namespace is now defined in the group.