Overloading for T and T'Class

[jgv@swl.msd.ray.com (John Volan)]

In Ada9X, is it legal to overload the same subprogram name for both
some tagged type T and its class-wide type T'Class?  For example:

	package P is
	  type T is tagged ... ;
	  procedure Op (X : in out T);
	  procedure Op (X : in out T'Class);
	  ...
	end P;

If this is legal, what would be the ramifications of doing this?
Would it even make any sense to do this?  If it did make sense, does
anyone have any thoughts as to where this might turn out to be useful?

This might seem like a strange question, but it's been nagging me for a 
while, and I'd appreciate whatever insights you folks out there might
have.  Thanks in advance!

					John Volan

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