Rolling back #227677: caused issues with node_save() after its race condition was resolved in #230029

#256285 by hass, mfer, tested by mfer: upgrade to jQuery 1.2.6, fixing some JavaScript interaction bugs; also improves JavaScript performance

#272636 by evolvingweb, dvessel: add 'js' class to html tag in drupal.js instead of overwriting all its classes with 'js'

#230029 by killes: rework node saving code to remove possible race condition with node and node revision saves; solves duplicate key errors on busy sites

#170309 by Jaza, keith.smith, naquah, pwolanin, Nick Urban, Pasqualle: menu_set_active_trail() does not allways include all items; fixing breadcrumbs to include parants properly

#277677 by yched: fix drupal_write_record() to support updating columns to NULL; required to make CCK work without workarounds

#266596 by pwolanin: menu performance improvement to not localize menu items which are not accessible

#180646 by Heine, John Morahan: taxonomy_get_term_by_name() should use = instead of LIKE in query, to allow for % to be a free tag

#266367 by zeta z: improve code documentation on how modules should provide default theme hook implementation

- Patch #273761 by catch: removed inconsistent delete behavior of nodes.  It would leave comments, ratings, etc behind in the database.

#252921 by David_Rothstein and agentrickard: remove unused join, which caused column type compatibility problems with postgresql; improves postgresql compatibility

#257279 by robertDouglass and David Lesieur, tested by douggreen: removing an extra join which was not required in the do_search query; improves search speed.

- Patch #251402 by quicksketch: text can't be selected via click and drag when the Drupal drag and drop interface is present in IE7.

#252580 by Robert Douglass, Gerhard Killesreiter, flobruit: avoid division by zero, when all search weights are set to 0

#189568 follow up by dvessel and Desbeers: we need to unset the CSS file overriden so that it is not added on CSS aggregation

#238760 by Optalgin, boydjd, Damien Tournoud, pwolanin: reduce window for error in menu table rebuilding, only emptying the table once we have data to save to there

#217957 by yched, quicksketch: header cell removal is broken when headers use colspans (and a little bit of performance improvement)

- Patch #259463 by dmitrig01: notification e-mail for pending user registrations had blank subject line.

#241570 follow up by merlinofchaos: the previous patch was inverting the problem with theme preprocess functions

#200824 by sammys, justinrandell, Arancaytar, test by vladimir.dolgopolov: drupal_write_record() returns array in some error cases when it should just return objects

#258120 report by dag, patch my myself: l() attributes were not updated properly to Drupal 6 in theme_username()

- Patch #258128 by webchick: @parameter should be @param.  Gets the Most Trivial Patch of the Month Award.

- Modified patch #230374 by killes, jakeg, Eaton et al: corrected problem with form API caches not being flushed.  This could lead to performance issues.

- Patch #231132 by snufkin: fixed invalid XML-RPC error messages due to HTML tags being inserted in the message string.