Language switcher misses the languages that are not available for the viewed page.

The internationalization project is a really outstanding one, it really needs much of the support of this community, and I would like to take benefit of this new thread to thanks and congratulate the people who actively work on it.

This is a follow-up of the issue http://drupal.org/node/314721

It started basically with the same problem, but then focused on getting the right node reference during a translation.

Now, the problem is the following:

Note1: you have to have at least one multilingual book with at least some pages inside
Note2: you need to be logged in as administrator to reproduce as described
Note3: among the stated problems, #1, 3 and 4 did not seem to exist before solving the reference issue - this might help to locate thie issues.
Note 4: Before solving the node reference issue, it was still possible to create smothly a translation by switching the language just before clicking on "add transalation, which is no longer possible

S1) Go to a page that needs to be translated
problem #1 : the language switcher will miss the languages that are not yet available for this page.

S2) Clic on "translate"

S3) Clic "Add translation" for the language you are going to translate the page to
You get to the page for edition, the language selector is greyed, sticked on this language.
Make your translation or whatever

S4) Now, try to outline this page:
- You can only access books in the given language - Great
- problem #2: you cannot see any parent item: not the book itself nor any page inside
- set the outiline weight - OK

S5) Finally, you want to make someone else the author of this book page
(note this is a common practice as no ordinary human being can hande transalation at the current state of i18n module)
- probem #3: you get "An http error 404 occurred … user/autocomplete"
For me, this error occurrs when trnsalating from the default language. Translating from another one works

S6) Now, set it to a menu item and save
- problem #4: the menu item is not set.
- problem #4bis: your primary/secondary multilingual menus are totally messed up; But don't worry, it normally resumes after switching the different languages. (however I once found all menu items from all languages packed into the same default primary menu...)

S7) Re-edit the page

S8) Try to complete your outline job that couldn't be completed in S4 (problem #2)
It works

S9) Try to set the authoring information that broke in S5 (problem #3)
it works

S10) Try to reset the menu as desired and save (problem #4)
same behaviour. The menu feature doesn't work at all.