upgraded but now see strangely named tasks descriptions

I upgraded from 4.1 to 5.1a.  Now whenever anything is performed in vcenter the Recent Tasks has them named strangely.  Here are some examples:

xxx host.datastoresystem.computeDiskPartitionInfo.label not found XXX

xxx com.vmware.vcIntegrity.CheckNotificationTask.label not found XXX

Everything done has the "label not found" issue.  Other than the description, everything does work fine.