- Patch #20451 by Moshe: some ancient code was assuming that all apges in a book are of type 'book'.

    - permissions menu link updates in a number of modules help
    - anchor link fix in distributed auth help
    - "my account" link fix in user help
    - spelling correction in tracker.module help

- I also changed 'admin/access/perms' to 'admin/access/permissions'.

- Patch #16462 by Moshe: book pages slighty disobey the node_access system because they always return a value for book_access('update'). This simple patch causes us to use node_access when the user has a chance of being able to update the current page.

- Patch #15948 by matteo: the book module should call the nodeapi hook when printing printer-friendly pages.

- Patch #15843 by Ber: in book-pages node forms we use a delta of fifteen (-15 to +15) but in the book-outline admin we dont dewfine this, resulting in a default delta of ten. This should be consistent and thus both 15.

- Patch #14731 by chx: made it possible to rewrite node queries.

  We added a 'severity' column to watchdog():
    watchdog($type, $message, $link) --> watchdog($type, $message, $severity, $link);

    * Specify a severity in case you are reporting a warning or error.
    * The $link-parameter is now the fourth parameter instead of the third.

  TODO: document this in the upgrade guide.

- Bugfix: the book module incorrectly assumed that there is an active revision if n.moderate = 0.  We can (and need) to rewrite this when the revision changes hit core.  In essence, we need an efficient query to retrieve the 'last puslished revision that is not in the moderation queue'.

   * Less logic in theme code.
   * Encourages use of the menu system.
   * Easier to find where a title or breadcrumb comes from in other people's code because there are less places to look. Look in menu and then grep for the appropriate set function. Looking for calls to theme_page() is hard because there are too many of them.
   * Very slightly more efficient.

- Removed some cruft: left-over xxx_help_page() functions.

- Patch #13443 by Moshe: got rid of the semi-implemented 'page link' feature. All themes currently support primary and secondary links so page links are now deprecated.  Check your contributed modules and update them accordingly.

- Patch 13180 by chx: renamed check_query() to db_escape_string() and implemtented it properly per database backend.

  Read the manual for pg_escape_string:  "Use of this function is recommended instead of addslashes()." Or read sqlite_escape_string: "addslashes() should NOT be used to quote your strings for SQLite queries; it will lead to strange results when retrieving your data."

- Modified patch #8552 by Gerhard: added 'add child page' link to book pages you can edit.

- Patch #12783 by Stefan: various small consistency/usability improvements.

- Patch #10632 by Gerhard: the book permissions in today's cvs are not consistent with the rest of Drupal. We have a "maintain books" and a "edit own book pages" permission. All other modules have a "create foo" permission. Thus the existing "maintain books" permission should be renamed to "create book pages" and a new "maintain books" permission should be introduced that allows editors to update book pages they haven't created themselves even without having "administer nodes" permission.

The primary goal of this patch is to take the 'custom' and 'path' columns of the block overview page and make them into something understandable. As of Drupal 4.5 'custom' lacked an explanation which wasn't buried in help text and path required dealing with regular expressions.

Every block now has a configuration page to control these options. This gives more space to make form controls which do not require a lengthy explanation. This page also gives modules a chance to put their block configuration options in a place that makes sense using new operations in the block hook.

The only required changes to modules implementing hook_block() is to be careful about what is returned. Do not return anything if $op is not 'list' or 'view'. Once this change is made, modules will still be compatible with Drupal 4.5. Required changes to core modules are included in this path.

An additional optional change to modules is to implement the additional $op options added. 'configure' should return a string containing the configuration form for the block with the appropriate $delta. 'configure save' will come with an additional $edit argument, which will contain the submitted form data for saving. These changes to core modules are also included in this patch.

  TODO:
   + Update Doxygen hook list (if required).
   + Document this in the developer's upgrade section.

- Patch #11947 by puregin: ensured that a book node's weight is captured when the book node lists returned by book_location() and book_location_down() are generated. This information is required when selecting next page candidates in book_next().

Note that book_location_down() was missing an explicit field b.weight in the SQL SELECT statement, but this value would usually be supplied implicitly because it is used to ORDER the result.

- Patch #11728 by Uwe Hermann: fixed some typos in the code comments, Doxygen documentation and screen output.

  Uwe: I dropped the 'iff' chunks as 'iff' stands for 'if and only if'.

- Mofified patch #8862 by puregin: improved book module documentation.

- Fixed bug #11312: menu caching to aggresively.  I did not apply the proposed
  patch but moved the menu-logic to the $may_cache clause and added some checks
  to avoid SQL overhead.  I think this is the most performant solution.

- Code improvement: removed some redundant code from the book module.