XAJAX team has release a new version of its library for PHP and ajax: XAJAX 0.2.5

xajax 0.2.5 has been created as a bridging step to xajax v0.5. xajax 0.2.5 aims to be forwards and backwards-compatible with xajax versions, while at the same time providing important security updates that have been lingering around in the xajax codebase for a while
It's been just over one year since we released our last version of xajax and it was about time we released another version. Work on v0.5 has been going well and we're almost ready for a release, but there were a few things that couldn't wait for the next version. Thats where xajax 0.2.5 steps in. For a start, we're getting things ready for you to move over to the new xajax v0.5 syntax by letting you use easier to use methods to respond to client requests. We've also fixed up a few bugs that have been lingering around and been annoying everyone for some time. Last but not least, we've fixed up a couple of important security vunerabilities.

I've made a new version of the mambot http://www.xajax-joomla.com/

Just remove the mambot and install this new version XAJAX System Mambot For Joomla v0.2.zip (look in my download section). I am running also now OpenComment 3.0.30 with the latest version of Xajax 

NEW:  you can disable the paging algorithm... so users do not have to click many times to go through all comments
NEW: admin can unpublish comment in frontEnd
NEW: more security check for admin AJAX functions
BUG: language not correct in frontend, fallback to english. was only if register globals off
BUG: newest comment first fix ... submitted by Fanno
BUG: bbcode support fix ? submitted by Fanno
BUG: small admin fix submitted by Fanno
BUG: IMPORTANT FIX do not allow visitor to delete comment - submitted by Fanno

You will be able to see the latest version running at demo.waltercedric.com soon
Install file in order specified by number...

    * 001.mambot_xajax4joomla.plugin.zip
    * 002.component_opencommentxx.yy.zz.zip
    * 003.mambots_opencommentxx.yy.zz.zip

The optionnal directory contains modules and components not required by Opencomment depending
on your setup

Against spammers:
(You only need to use one of these)

/optionnal/com_securityimagesxx.yy.zz.zip
  install com_securityimages security against spammers using CAPCTHA. May annoy users as they have to solve a puzzle

/optionnal/com_askimetxx.yy.zz.zip
  install com_askimetxx.yy.zz sagainst spammers using askimet webservices. Transparent for users.

/optionnal/module_opencommentlatestxx.yy.zz.zip
  A module for displaying the latest 10 comments
 

Issues? Joomla component troubleshooting
Please read http://www.waltercedric.com/content/view/1059/247/

Bundle:

• component (require)
• mambot (require)
• module (optionnal)

Please post you feedback at http://forums.waltercedric.com

3.0.21

• BUG: Small bug during settings save, the key opencomment_cleanupPostingUsersHistoryfromDatabaseAfter was set to blank
• NEW: new admin menu entry: View last posting, it show the content of table which contains last comments entries, OpenComment use it internally for avoiding users to post more than one in the allowed interval You have set.
• BUG: (regression) Admin menu entry: akocomment migration was no more working
• BUG: on some Joomla! install including mine ;-) wenn a mambot for replacing BBCODE (mos_smilies) were active, the javascript code javascript:openCommentNewEntry(...  was replaced by :-)penCommentNewEntry(

3.0.20
The code is getting better at each release...but may have encounter some regressions. So Your feedback is welcomed

• NEW: use the project xajax-joomla.org which let you run multiple XAJAX modules or components  (1)
• BUG: encoding problem should be defacto solve as XAJAX now use Joomla encoding 
• NEW: Version able to run on hardened PHP server: Register globall OFF (php.ini) + SAFE_MODE On (php.ini) + RG_EMULATION = 0 (Joomla globals.php). Should solve different issues like "You are trying to hack me"
• BUG: User homepage was not saved or displayed
• NEW: Better CSS support  (see OpenCommentUpdaterA)
• NEW: code refactored and enhance compatibility during sanitization of inputs (mysql_real_escape_string was not existing on all host) see OpenCommentSanitizer
• BUG: minor translations problem.
• NEW: german translations credits

Note: You MUST install the Mambot mambot_xajax4joomla.plugin.zip and activate it prior the installation of OpenComment. That may still disturb others components which prefer to include XAJAX by themselves...
Next version (3.0.21) will have

• Correct all new bugs
• Administration functions (delete then edit)
• Report abuse button.

3.0.15

• NEW: full german translation courtesy of Joern Gerken successwiki.com
• BUG: can not update value of  opencomment_cleanupPostingUsersHistoryfromDatabaseAfter (default was 10 minute)
• BUG: \r\n and/or \n (Newline) were not translated into <br />
• BUG: The openComment menu shows an entry called "editOpencommentCSS", which does the same as "Edit newpost feedback template".
• OPEN:  Warning: mysql_errno(): supplied argument is not a valid MySQL-Link resource
  

  I can not reproduce it on XAMPP 1.5.4a  ( Apache 2.2.3 - MySQL 5.0.24a - PHP 5.1.6 & PHP 4.4.4 ) with following PHP settings: safe_mode = On register_globals = Off and Joomla!  define( 'RG_EMULATION', 0 );   (from globals.php)

3.0.14
A minor release because a lot of thing need to be done behind the scene....

• NEW: AJAX Encoding  can be freely defined by user. This is a temporary solution, ideally it must be read from Joomla Language file.
• BUG: the "write comment only visible for first article" is solved.
• BUG: fully translated Administrator panel and localized in English.php. File now contains 370 keys

Soon:

• PENDING prio1: Ajax problem still persist that it did not work with Jim IM and whosonlineext modules. it will be soon  mandatory to install and publish a Mambot before using OpenComment. Ive tried to use it,  but it does not currently work. The encoding problem should solve itself, because the mambot will use your Joomla! encoding.
• PENDING prio2: Add  a mode feedback, telling the user if he is replying or submitting a new comment.
• PENDING prio1: putting presentation layer in PatTemplate file (Priority 2 but needed for speeding output as code is a mess and doing too much string concatenations)

3.0.12

• NEW: Search function in query control panel
• BUG: Found latest error in installer file
• BUG: No more <? starting tag but <?php     was revealed by users using PHP5 and Magic_Quote = OFF in PHP.ini
• BUG: Solve small bugs in administrator panel.
• NEW: A new settings:  Users Posting History, how long a user can not submit a new comment in the same article This do not let user press submit more than once. Default is 10 minutes. Algorithm is based on a new table opencomment_postinghistory which store ip, referrer, article id
• NEW: No more using the PHP mail API but the Joomla! mosMail(), this solve also the bug  HTML feedback sent as text.
• BUG: Internet Explorer layout no more disturb by missing columns.
• BUG: Comment footer is looking better.
• PENDING: Encoding problem, problem occurring in IE under some conditions, not in FIREFOX. Since AJAX do not access to Joomla APIs, I've put an encoding selector in the administrator panel (utf-8 or iso-8859-1)
• PENDING: Add  a mode feedback, telling the user if he is replying or submitting a new comment.
• PENDING: putting presentation layer in PatTemplate file (Priority 2 but needed for speeding output as code is a mess and doing too much string concatenations)

3.0.10

• initial