Pop veteran SIR Elton John is refusing to slow down ahead of his 60th birthday next month (25MAR07) - he's working double shifts in Las Vegas. As well as preparing for his spectacular birthday concert at New York City's Madison Square Garden, performing regular concerts, and working on a theatre production of PRISCILLA, QUEEN OF THE DESERT, the busy star somehow found time to fit two shows into one evening earlier this week (begs12FEB07). After wowing crowds at Caesars Palace, the ROCKET MAN singer had a quick changeover before joining Prince at nearby hotel the Rio, where they thrilled fans with a duet of Beatles hit THE LONG AND WINDING ROAD, according to the New York Daily News.