Haven't changed password, default "00000000" doesn't work!?

I have never been able to use any of the password protected functions of my D900. It arrived factory sealed, fully unlocked, but when I try to use the password in the manual and on the samsung website (eight zeros) it says it's incorrect. This is not the sim-lock password, it's the password for things like deleting all contacts from the sim card (i accidentally duplicated them all from the phone memory so I had to delete all the duplicates manually in the end!)

I'm totally sure I never changed the password does anyone know if the default password is actually something other than "00000000" (8x zero)?

Thanks for your ideas!