Despite rumors that Paul McCartney and fianc&#233e Heather Mills were to tie the knot yesterday in an Irish castle, Reuters reports that the nuptials have not yet taken place. "We are told vaguely it is next Tuesday, but it is all secret. I have to keep it dead secret," said the castle's owner, Sir John Leslie. He teased that ex-Beatle McCartney, 59, and Mills, 34, "might do something at the last minute or change it. You never know."