Need support in patching i18nmenu for 6.x

Hi,
since no one has cared about the non-functioning i18nmenu in 6.x. for a long time, I tried to patch it myself, but I'm stuck. If some developer who knows what i18nmenu should finally do is willing to support me, I might be able to get things fixed.

I expect localized menus to work as follows:
I create a new page "E" in english language with a menu title "English" in my custom menu. Then I localize that string to "German". Then I create a german translation "G" of my page and don't chose a menu title for it (otherwise I would end up with two menu entries). Now I expect to see "English" in my menu, pointing to E. When I switch language to german, I expect to see "German" in my menu, pointing to G.
If I have some children of the "English" menu entry that point to language neutral pages, I expect those children to stay when switching language, i.e. see the children below menu entry "German", too, since it is the same menu entry, just localized. That would be the main difference to giving the german translation of the page an own menu title and thus a different menu entry!

Is that correct? If not, forget the rest of this post and explain to me how it should work :-) I cannot think of a different way that makes a difference to chosing an own menu title for every translation (and then I didn't need i18nmenu).

What I did so far:

• increased module weight of i18nblocks.module (and to be sure, also i18nmenu). Otherwise nothing ever localizes because i18nblocks_theme is responsible for calling i18nmenu_translated_tree for every block which finally translates menus. But the system module is loaded after i18nblocks and does return array_merge(drupal_common_theme(), array(..., thus rewriting the blocks theme from i18blocks with the defaults from drupal_common_theme.
• Now i18nmenu_localize_tree tries to replace $tree[$index]['link']['title']. But that never happens
  if we have language mode 'simple' (current language and no language) and our current language is german. Then we get only the list of menu entries that point to nodes with language german or no language.
  But our german page G has no menu entry, only the english page E. Therefore I set i18n_selection_mode('off'); in i18nmenu_translated_tree to fetch all menu entries (could do better like fetching only those for that a translated version of the current language exist).
• Now I filter the menu entries in i18nmenu_localize_tree as follows:
  • if the node the menu entry points to has a language which is the current language, keep the entry
  • if it has no language, keep the entry (for mode 'simple',. must be finegraned for other modes)
  • if node has a different lang than the current, localize the title with the tt function (original code of i18nmenu_localize_tree ). If the title does not localize, unset the menu entry. We can't show it if there is no localized string for our current language
  • if the menu title localizes check for a translated version of the node in our language (using translation_translation_link_alter for $link['href']. If a translated version for current language exists, I replace the href by
    $tree[$index]['link']['href']=$trans_links[$current]['href'];
    so that the localized menu entry points to the translated version.
• That does work for top level menu entries. But if the original "English" menu entry has menu childen, the localized menu entry "German" has not, and as far as I see things start to go wrong in menu_tree_page_data. When I'm viewing page "G", the submenu should unfold below the "German" menu. But menu_tree_page_data loads the "menu item corresponding to the current page" and then searches children for this menu item etc.

  BUT: our current page G doesn't have a menu entry, because menu item "German" is no a real, own menu item, but only the localization of the "English" menu. So no menu item is found for G and therefore no menu children are created for menu item "German".

Thus, the idea of a page and all translations being bound to one menu entry with localized menu title, cannot work this way.

But if we localize only the menu title without changing the href, then the menu title would change to e.g. "German" but still point to E instead of G. So this can't be the idea of localized menus I guess.

The only way it would work at the moment was to create only language neutral pages, localize their menu entries and write the content of all languages on one page. There was some patch or module that I currently don't find where you would write sth. like

==en==
This is shown when language is english
==de==
Das sieht man wenn die Sprache deutsch ist

so that only the part of the page matching the current language is shown.