Card cloning strangeness in 2.5.1

[Jerry Balzano]

I just unwrapped 2.5.1, started a stack, made a card, and then, in 
order to try a variation on the card design, I issued a familiar 
command in the message box:

	clone this card

...and nothing happened!  Not believing my eyes, I opened a new stack, 
tried it again, same result.

Went to 2.5, tried the move, it worked.  Relaunched 2.5.1, tried it 
again, no go.

Does this behavior replicate with others?  (I'm using a Mac, OS 10.3.7)

- Jerry