libpurple
- Improve sleep behavior by aggregation of longer timeouts on second boundaries to allow better power saving. (Arunan Balasubramaniam)
- Fix various crashes on exit.
- Make XML parsing more resilient to interactions with other libraries. This, along with the fix for libxml2 bug 564217, fixes the crashes on connect in XMPP with recent gst-plugins-bad (see #8830 for details).
- Many security related fixes

IRC
- Correctly handle WHOIS for users who are joined to a large number of channels.
- Notify the user if a /nick command fails, rather than trying fallback nicks.

MSN
- Fix a race condition causing occasional Pidgin crashes.
- Fix some errors about the friendly name changing too fast caused by MSN/Yahoo integration buddies.

XMPP
- Less likely to pop up a new conversation window in disregard of the “Hide new IM conversations” preference.

Yahoo
- Fix a crash when sending very long messages.
- Fix a bug where UTF-8 status messages get garbled when going idle.

libpurple:
* Fix a crash when removing an account with an unknown protocol id.
* Beta support for SSL connections for AIM and ICQ accounts. To enable, check the “Use SSL” option from the Advanced tab when editing your AIM or ICQ account. (Paul Aurich)
* Fix a memory leak in SILC. (Luke Petre)
* Fix some string handling in the SIMPLE prpl, which fixes some buddy name handling and other issues. (Paul Aurich, Marcus Sundberg)
* Implement support for resolving DNS via the SOCKS4 proxy (SOCKS4a).

ICQ:
* Fix retrieval of status messages from users of ICQ 6.x, Miranda, and other libpurple clients. (Daniel Ljungborg)
* Change client ID to match ICQ Basic 14.34.3096. This fixes publishing of buddy icons and available messages.
* Properly publish status messages for statuses other than Available. ICQ 6.x users can now see these status messages. (Daniel Ljungborg)
* Fix receipt of messages from the mobile client Slick. (David Jedelsky)

MSN:
* Fix transfer of buddy icons, custom smileys, and files from the latest Windows Live Messenger 9 official client. (Thomas Gibson-Robinson)
* Large (multi-part) messages are now correctly re-combined.
* Federated/Yahoo! buddies should now stop creating sync issues at every signin. You may need to remove duplicates in the Address Book. See the FAQ for more information. Thanks to Jason Lingohr for lots of debugging and testing.
* Messages from Yahoo! buddies are no longer silently dropped.
* We now save and use the CacheKey for ABCH SOAP requests.
* Don’t try to parse Personal Status Messages or Current Media if they don’t exist.
* Convert from ISO-8859-1 encoding to UTF-8 when no charset is specified on incoming messages. This should fix some issues with messages from older clients.
* Force sending the font “Segoe UI” if outgoing formatting doesn’t specify a font already.
* Queue callbacks when token updates are in progress to prevent two token update attempts from trampling each other.
* Fixed a crash on Windows when removing a buddy’s alias.
* Update the Address Book when buddies’ friendly names change. This prevents seeing an outdated alias or not seeing an alias at all for buddies who are offline when you sign in.
* Update tokens for FindMembership and ABFindAll SOAP requests.
* We no longer try to send empty messages. This could happen when a message contained only formatting and that formatting was not supported on MSN.
* Buddies on both the Allow and Block list are now automatically removed from the Allow list. Users with this problem will now no longer receive an ADL 241 error. The problematic buddy should now appear on the buddy list and can be removed or unblocked as desired.

XMPP:
* Resources using __HOSTNAME__ substitution will now grab only the short hostname instead of the FQDN on systems which put the FQDN in the hostname. (Matěj Cepl)
* No longer send a ‘to’ attribute on an outgoing stanza when we haven’t received one. This fixes a registration bug as described in ticket #6635.

Pidgin:
* Tooltip windows now appear below the mouse cursor. (Kosta Arvanitis)
* Tooltip windows now disappear on keypress events. (Kosta Arvanitis)
* Tooltip windows no longer linger when scrolling the buddy list. (Kosta Arvanitis)

Finch:
* Allow rebinding keys to change the focused widget (details in the man-page, look for GntBox::binding)