Is there a Terminal command that will force open the DVD tray? Is there a command I can enter in Terminal that will force eject a CD or DVD? One that will always work, equivalent to a "Force Quit" for an app?

I have an intermittent problem getting the DVD in my Mac Pro to eject. Right now the only solution is to do a full restart, but that is obviously not always convenient. I'm hoping there is a workaround to this through the magical power of UNIX...
First of all, try the "nice" way using the drive utility

drutil tray eject


If this doesn´t work (probably because the system can´t unmount the volume), the following command will forcefully unmount the Volume with name "untitled" (make sure you´re using the right mountpoint!!):

hdiutil detach -force /Volumes/untitled