I realize now I made a critical error when installing and running the Flex Builder 3 evaluation copy - when asked whether I wanted standalone or (existing) Eclipse plug in, I said standalone. I actually needed to do the plug in option, so I could leverage existing Java projects on the server. In other words, I need to do combined Flex/Java projects.
I've tried going the other way - adding all the eclipse components to the standalone FB3 instance, but I'm having all sorts of issues.
Is there any way to switch the mode without screwing up my trial period? I have to build a prototype to justify buying it, which I can't do if I hose up the eval, which just started.