When you creating a classic-tween and you add an ease to it using the ease editor – it works fine, BUT! If you want to insert a keyframe inside that tween range it totally messes the spacing! It’s a tremendous bug which keeping me and many other animators I know away from those versions.
I truly hope that in Flash CS6 that continuous bug will be gone and finally I will be able to upgrade my old Flash cs3!
The forums are not the place to post bugs/wishlist items.... Adobe rarely visits here. Use the link below, though it is probably too late for CS6 since CS6 appears to be on the verge of release - you can probably get a trial version of it and see for yourself.
Adobe - Wishlist & Bug Report
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