Comment 54 for bug 397734

Since that the case, I think that kernel defauit ought to be changed by patching the kernel.
The devicekit solution is really not full answer

Btw, folks, to workaround this, you can add to boot scripts the

'echo 0 > /proc/sys/dev/cdrom/lock' as suggested in one comment above.

With this, cdrom eject button ought to work.