ActionScript Vector casting inconsistency?

When a Vector is casted like this...

var v1:Vector.<String> = new Vector.<String>();
 v1.push("foo");
 
 var v2:Vector.<Object> = Vector.<Object>(v1)
 
 v1.push("bar");
 
 trace(v1);   //foo,bar
 trace(v2);  //foo
 

... a copy of the Vector is created, as you can see in the trace output.

But when you change line 3 to...

var v2:Vector.<*> = Vector.<*>(v1)
 

... no copy is created, both v1 and v2 point to the same object, trace outputs will both be "foo,bar".

Why that? Shouldn't there somehow be a consistent behaviour?

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