I am convinced that MD11's may be able to dump fuel, but can any MD pilot perhaps confirm.
Regarding the A330 dumping capability (1 ton/min) - this particular one was the A330-200 and it seems like it is not standard on all fleets. Emirates operates a few of them and apparently with the dump capability. Don't know if that was a company specific request for the option as they operate out of Dubai where temps are very high and pressures are low in summer. On some of the runways overhere, due to obstacles in the climb out, certain types of aircraft have up to an eight ton fuel penalty if they have to depart from a particular runway and therefore these guys would always request the opposite end for departure if traffic and wx permits.
Cheers
Fart