Try FDT as well, or at least the trial. Im a big fan and many heavyweight flash devs out there use FDT for Flash and Flex work - it's like having Flash CS4 and Flex Builder, but better than both 'cause Flash's code IDE is only a setup up from a text editor and Flex Builder is not to my standards for and IDE.
Try the FDT plugin for eclipse. Also check out Lee's 'Pimp my Eclipse' parts 1, 2 and 3 http://theflashblog.com/?p=483 Alan
