Eclipse has a really nice feature which allows through a keyboard shortcut the ability to update the imports required for your code.
I liked that, but didn't know of anything that did the same thing for Ada source code.
I have began creating a script which does this, and you can use programs to run it, (perhaps port it to a plugin for a program).
I called it Ada-Withs (I know it sounds pretty boring)
It's not complete, but right now the script will pull out all packages used in the program.
If you want to give it a try go for it. If you want to mess with it, pull and let me know if you have any improvements.
The link above does go to it but here is the full url as well: