Aspiring rapper KEVIN FEDERLINE has reportedly delayed the release of his debut album so he can add a duet with his pregnant wife Britney Spears to it. Former dancer Federline is anxious for PLAYING WITH FIRE to be a success, so has postponed its planned release next month (JUL06). An insider tells British newspaper The Sun, "He will be rapping over her singing. But people are warning it could be a career move for Britney."