It works!
Still a few issues are left, nothing tough to fix.
Checkout the project homepage http://code.google.com/p/flexlib/
A new swc should be released soon (I guess as soon as the few broken components get fixed), for now you’ll have to do a fresh subversion checkout to get the flex4 compatibility.
Enjoy!
Edit: It didn’t work for long, released flash builder comes with a few api changes that break the current codebase. Expect those to be fixed by this evening. Hopefully.
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