I have been playing a bit with BlazeDS, the new open source release of Adobe LiveCycle Data Services. Overall, it looks good to me, as the open source release has all the features I need. Unfortunately, I stumbled onto the fact that Flex 2 SDK doesn’t work with the BlazeDS messaging features, and I have a small project where I can’t upgrade to Flex 3.
When trying to produce a message the following fault is thrown:
“Destination ’simple-topic’ requires FlexClient support which was introduced in version 2.5. Please recompile the client application with an updated client framework.”
There isn’t actually a 2.5 version of Flex SDK. So, I enlisted some help from Adobe’s James Ward. He did some digging with the Flex engineering team, and after sometime was able to provide me with a work around. However, with that work around came the clarification that ‘BlazeDS is not compatible with Flex 2.’ I was in the dark to this fact and don’t believe that Adobe is publicizing it. I am ok with BlazeDS not supporting Flex 2 (it sounds like the next version of LCDS will have the same limitation), but I wish Adobe would have told me this up front. 
