MediaWiki internal error.

Original exception: [d4907c9f] /index.php?title=Kiskoken_(System)&action=edit Exception from line 517 of /home1/silver/public_html/wiki/includes/EditPage.php:
Backtrace:
#0 /home1/silver/public_html/wiki/includes/EditPage.php(407): EditPage->displayPermissionsError(array)
#1 /home1/silver/public_html/wiki/includes/actions/EditAction.php(50): EditPage->edit()
#2 /home1/silver/public_html/wiki/includes/Wiki.php(428): EditAction->show()
#3 /home1/silver/public_html/wiki/includes/Wiki.php(292): MediaWiki->performAction(Article, Title)
#4 /home1/silver/public_html/wiki/includes/Wiki.php(588): MediaWiki->performRequest()
#5 /home1/silver/public_html/wiki/includes/Wiki.php(447): MediaWiki->main()
#6 /home1/silver/public_html/wiki/index.php(46): MediaWiki->run()
#7 {main}

Exception caught inside exception handler: [a1f587a9] /index.php?title=Kiskoken_(System)&action=edit Exception from line 222 of /home1/silver/public_html/wiki/includes/Hooks.php: Detected bug in an extension! Hook Cite::checkRefsNoReferences has invalid call signature; Parameter 2 to Cite::checkRefsNoReferences() expected to be a reference, value given
Backtrace:
#0 /home1/silver/public_html/wiki/includes/GlobalFunctions.php(4013): Hooks::run(string, array, NULL)
#1 /home1/silver/public_html/wiki/includes/parser/Parser.php(396): wfRunHooks(string, array)
#2 /home1/silver/public_html/wiki/includes/cache/MessageCache.php(1070): Parser->parse(string, Title, ParserOptions, boolean)
#3 /home1/silver/public_html/wiki/includes/Message.php(963): MessageCache->parse(string, Title, boolean, boolean, Language)
#4 /home1/silver/public_html/wiki/includes/Message.php(661): Message->parseText(string)
#5 /home1/silver/public_html/wiki/includes/Message.php(720): Message->toString()
#6 /home1/silver/public_html/wiki/includes/OutputPage.php(2268): Message->parse()
#7 /home1/silver/public_html/wiki/includes/exception/PermissionsError.php(55): OutputPage->showPermissionsErrorPage(array, string)
#8 /home1/silver/public_html/wiki/includes/exception/MWExceptionHandler.php(44): PermissionsError->report()
#9 /home1/silver/public_html/wiki/includes/exception/MWExceptionHandler.php(139): MWExceptionHandler::report(PermissionsError)
#10 /home1/silver/public_html/wiki/includes/Wiki.php(454): MWExceptionHandler::handle(PermissionsError)
#11 /home1/silver/public_html/wiki/index.php(46): MediaWiki->run()
#12 {main}