Here is a bug (or maybe I expected too much?) that caught me off-guard when I am trying to customize Eclipse perspective:
After opening "Aptana" perspective, I selected menu "Window"->"Save Perspective As", and saved perspective as "My Workspace" so that I can make changes without ruining the original Aptana perspective. Then I noticed that after I restart Eclipse "Code Assist Profiles", "Outline" and "Actions" no longer work. It took me a while to figure out the root reason is that I am not using THE "Aptana" perspective. After I select back to "Aptana" perspective, everything works again. In my opinion, this is not how perspective supposed to work. I should be able to make a copy of their perspective and add my own customizations.
I have reported the bug to Aptana: http://www.aptana.com/trac/ticket/3971