Jordan,
Feed.java imports three Flex messaging classes:
1) flex.messaging.MessageBroker
2) flex.messaging.messages.AsyncMessage
3) flex.messaging.util.UUIDUtils
These classes must be included in the build path. If you have a license for LiveCycle Data Services ES, these classes are available in ../WEB-INF/lib. If you do not have a license for LiveCycle Data Services ES, you can get these classes in the open source version of Data Services ES called BlazeDS.
http://opensource.adobe.com/wiki/display/blazeds/BlazeDS/Steve