How can I create aspects for Material Definitions and its properties?

Tried to use IMaterial/AddAspect but could only get a following error message:
"Failed to execute method defined in activity 'AddAspect'. Exception : No such aspect 'Aspect1' for object type 'MaterialDefinition'."
Tried "AddPropertyAspect" as well with the same result.

Does anybody have any experience of working with aspects?