No, never mind - anyway, on the GBA English Super Mario Advance 4, the Princess's letter after World 3 reads as follows:
Greetings,
You can stomp on your enemies using Goomba's shoe.
I have enclosed a jewel that helps protect you.
Princess Toadstool
Yeah, I always thought it was called Kuribo's Shoe, but obviously not.
Cheers,
Matt
Mountain Dew or Crab Juice? Oh, I can''t take it any more!
You got a toilet in there? "No, toilet in tower. Tower!"