JAWS ARIA-Support

In case it's helpful, attached is a document that specifies how ARIA is being interpreted by Freedom Scientific and how it is being implemented within JAWS.

There is something that jumped out at me, this being:

Aria-busy: "In Firefox, an element marked as aria-busy is omitted from the accessibility tree for the page."

This looks to me like a JAWS bug, aria-busy should not be used to replicate aria-hidden.
Reference: http://www.w3.org/TR/wai-aria/states_and_properties#aria-busy
And http://www.w3.org/TR/wai-aria/states_and_properties#aria-busy
Where it states the following:
"* In ATK/AT-SPI and IAccessible2, the container-live, container-relevant, container-busy, container-atomic object attributes SHOULD be exposed on the accessible  event object, providing the computed value for the related WAI-ARIA properties. The computed value is the value of the closest ancestor."

My understanding is that aria-busy='true' simply indicates that a live region should not be treated as live until set to 'false', which appears to be supported in the UAIG, stating:
"WAI-ARIA         has provided a collection of properties that allow the author to identify         these live regions and how to process them: aria-live, aria-relevant,         aria-atomic, and aria-busy."

Is that correct?

Thanks,
Bryan