The correct is ArrayCollection > GroupCollection > SummaryRow
The order will be implemented on GroupCollection.
Example and documentation: http://livedocs.adobe.com/flex/3/langref/mx/collections/SummaryRow.html
Thanks for the response Stephan,
I tried sorting the GroupCollection after populating it, but it dosen't have that option. (ex: gc.sort dosen't exist) // gc is the id of the GroupingCollection
I'm pretty sure sorting the ArrayCollection first then passing it to the source of the gc. is the way to go, My Problem is: gc.refresh() which rearranges the sorting randomly. I need the refresh for it to populate/render immediately.