I just upgraded from MediaWiki 1.9.1 to 1.12.0. PHP 5.0.4 (apache2handler) MySQL 4.1.20-log Everything appears to work fine, except for when trying to edit using the [edit] option located on the far-right of any page. I can use edit located on any tab fine, but if I click [edit] on far-right of any page, I get: Invalid h node passed to PPNode_DOM::splitHeading Backtrace: #0 /var/www/html/intranet/wiki-it/includes/Preprocessor_DOM.php(1348): PPNode_DOM::splitHeading() #1 /var/www/html/intranet/wiki-it/includes/Parser.php(4605): PPNode_DOM->splitHeading() #2 /var/www/html/intranet/wiki-it/includes/Parser.php(4675): Parser->extractSections('{| width="100%"...', '2', 'get', false) #3 /var/www/html/intranet/wiki-it/includes/EditPage.php(193): Parser->getSection('{| width="100%"...', '2', false) #4 /var/www/html/intranet/wiki-it/includes/EditPage.php(982): EditPage->getContent(false) #5 /var/www/html/intranet/wiki-it/includes/EditPage.php(473): EditPage->initialiseForm() #6 /var/www/html/intranet/wiki-it/includes/EditPage.php(323): EditPage->edit() #7 /var/www/html/intranet/wiki-it/includes/Wiki.php(444): EditPage->submit() #8 /var/www/html/intranet/wiki-it/includes/Wiki.php(48): MediaWiki->performAction(Object(OutputPage), Object(Article), Object(Title), Object(User), Object(WebRequest)) #9 /var/www/html/intranet/wiki-it/index.php(90): MediaWiki->initialize(Object(Title), Object(OutputPage), Object(User), Object(WebRequest)) #10 {main} Any ideas? This did not happen on 1.9.1. Thanks, Shannon