If you upgraded your Ubuntu on an IBM T40 Laptop only to find out that there is no sound anymore, you’re not alone in this
Follow the bug report for more information !
Edit 2008-05-11 : As of today I don’t have this problem anymore … update your machine if you haven’t yet !
Edit 2008-06-22 : Sound vanished again … I really need to look into this before this drives me crazy !!
Sound seems to come back and vanish unpredictably reboot after reboot …