SPAM MEANS A TIN OF DODGY MEAT WITH A KEY ON THE SIDE.
"No not mail, that came through the door,
It fell to his feet when it hit the floor.
Inside the letter, were many more, made words,
He didn�t read them but instead he heard
�A tin of SPAM with an opening key, is the only way to enter me�
The old man took the key from the tin and before he knew it had entered it"