#323438 by emok, chx, mfb: uploaded files become arrays in previews, so object property checking will not work on them (from PHP 5.2.12+)

#587568 by Berdir, yhager: improve PHP 5.3 compatibility by using hook_nodeapi() the right way in node_search()

#229051 by jaydub, ainigma32, Josh Waihi, Dave Reid, druido, bellHead: solve top visitors pagination issues in statistics module with postgresql

#266488 by MadHarold, nbz, Damien Tournoud, sbandyopadhyay: fix some errors in username validation, clean up code style and add missing support for apostrophes

#362256 by pwolanin: backport poll module vote number form access handling from D7, avoid clearing vote numbers when editing a poll

#770598 by greggles, grendzy: move user login failure attempt logging to user_authenticate() to have unified logging with all kinds of authentication schemes, including blogapi

#462628 by Heine, pwolanin, dww: better documentation for taxonomy_form() to avoid possible security issues from contributed code

#722190 by bjaspan: avoid infite recursion in filter_list_format() even if the database has broken data under Drupal

#261258 by Damien Tournoud, David_Rothstein, pwolanin: node_save() could result in broken data with certain database configurations when log messages are not included

#704158 by mikeytown2, marvil07 and myself: fix notice in user_preferred_language() when the user has no preferred language yet

#422218 by salvis, sun: forum_load() should load the forum term id for a forum node, not just any term id it is related to

#604290 by JeremyFrench: speed up initial loading of user admin page considerably, when no filters are used

#212236 by wrwrwr: move empty paragraph handling to after other paragraph operations are done in _filter_autop()

#720516 by Dave Reid: taxonomy_get_term() and taxonomy_vocabulary_load() cannot restore their internal caches, therefore cannot be used in testing

#669554 by dww: reduce memory use of update module by only saving attributes update module needs from .info files

#409676 by mrfelton: remove watchdog message when JS files are parsed by locale; had minimal debugging value

#358315 by neochief, Damien Tournoud, andypost: drupal_lookup_path() does not respect path alias ordering when older aliases are retained

#696052 by Dave Reid: locale module variables are not properly uninstalled when the module is removed, causing fatal errors (backport of #347288)

#396388 by jmpoure, Alex_Tutubalin, Shiny, andypost,: rework comment ordering subquery to be SQL standards (and therefore PostgreSQL) compatible

#287063 by mkalkbrenner, mikeryan: avoid node_delete() 'leaking' memory via node_load() caching (eg. when multiple nodes are being deleted)

#251792 by pwolanin, Damien Tournoud, slantview, c960657: added a locking framework for long running operations; solves rebuilding issues with menus and the locale cache

#673974 by sun: PHP notice when mass-unpublishing or deleting comments, and wrong form validation redirect

#644482 by hass (backport of #452936): use TRUNCATE to do full cache clearing, which results in a dramatic speed increase

#280319 by robertDouglass: search_box_form_validate() is referenced in search form, but does not exist

#528204 by rfay, drewish: menu item sorting should be case insensitive; lowercase titles for sorting