VCloud API does not support this type of information, so not sure this is the best place to get an answer.
However in looking around a little it does seem that the data you need should be available via the vCenter API. (Looks like you need to query the events in the system and then do a little filtering)
Example that might help: http://www.lucd.info/2010/06/22/events-part-8-vmotion-history/