#360605 by Berdir et al.: make Drupal core work with PHP 5.3.0 out of the box (fixes for incompatibilities introduced with PHP 5.3.0)

#193383 by JirkaRybka, Arancaytar, Bart Jansens, gpk, TheRec: check correctly for function_exists() on set_time_limit() instead of infering that safe_mode has an effect on it or that that is the only thing which might disable time limit setting

#292565 second follow up by John Morahan: fix login destination again on 403/404 pages and make the search form work there if displayed

#534480 by solotandem, jhodgdon: fix phpdoc documentation of what $delimiter means in drupal_get_content()

#480044 by JohnAlbin: fix system component listing lookup priorities, so the sites/all/* items will override the profile shipped items as documented

#280240 by skiminki, casperbiering, anypost, pwolanin: Only add Content-Length if we actually have any content or if it is a POST or PUT request.

#310139 by fonant, c960657, pwolanin: drupal_urlencode() and Drupal.encodeURIComponent was used to encode query strings and other components it should not have been used for

#482646 follow up by Dave Reid: only check the db prefix for simpletest if it was a string (not running a multisite)

#482646 by Dave Reid: For proper HTTP query simpletesting, we should pass on the instance identifier (database prefix).

#452704 by andypost, catch: Names of compressed CSS and JS files should have a prefix, so that names starting in ad* will not happen. Those are easily blocked by firewalls, Firefox's Adblock, etc.

#454992 by sun, bengtan: _drupal_flush_css_js() should not have 'q' as a possible CSS query character, since that is the Drupal path name character too

#292565 by grendzy, John Morahan, Jody Linn: remove path munging on 403/404 pages, which caused problems for login redirects

#203323 by JirkaRybka, robertgarrigos, lilou, thePanz, c960657, sun: move the LANGUAGE_* constants to bootstrap.inc and remove several defined() checks on them now that they are always defined

#356721 by c960657, Dave Reid: remove static caching of the clean URLs setting in url() to help automated tests; the setting is cached through variable_get(), which however allows altering of the setting

#220559 by eMPee584, Desbeers, Damien Tournoud: only ever add the active class to links in l() and theme_links(), if the language was set and is the current language or if the language was not set on the link

#245990 follow up by Damien Tournoud, David_Rothstein, pwolanin: Move back to an internal URL check for HTTP request checking and make the request checking less intrusive on what requests can be accomplished

#345167 by JacobSingh, pwolanin, Heine: drupal_http_request() includes an extra CRLF, not conformant to HTTP specs