MediaWiki internal error.

Original exception: [54947e22] /wiki-pl/Specjalna:Linkuj%EF%BF%BD%EF%BF%BDce/Historia_polskich_Misjonarzy_na_Madagaskarze Exception from line 205 of /usr/www/users/nicollb/famvin-org/wpl/includes/Wiki.php: The requested page title was invalid, empty, or an incorrectly linked inter-language or inter-wiki title.
It may contain one or more characters that cannot be used in titles.
Backtrace:
#0 /usr/www/users/nicollb/famvin-org/wpl/includes/Wiki.php(602): MediaWiki->performRequest()
#1 /usr/www/users/nicollb/famvin-org/wpl/includes/Wiki.php(467): MediaWiki->main()
#2 /usr/www/users/nicollb/famvin-org/wpl/index.php(49): MediaWiki->run()
#3 {main}

Exception caught inside exception handler: [7a2ee6e1] /wiki-pl/Specjalna:Linkuj%EF%BF%BD%EF%BF%BDce/Historia_polskich_Misjonarzy_na_Madagaskarze Exception from line 212 of /usr/www/users/nicollb/famvin-org/wpl/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 /usr/www/users/nicollb/famvin-org/wpl/includes/GlobalFunctions.php(3877): Hooks::run()
#1 /usr/www/users/nicollb/famvin-org/wpl/includes/parser/Parser.php(396): wfRunHooks()
#2 /usr/www/users/nicollb/famvin-org/wpl/includes/cache/MessageCache.php(1042): Parser->parse()
#3 /usr/www/users/nicollb/famvin-org/wpl/includes/Message.php(843): MessageCache->parse()
#4 /usr/www/users/nicollb/famvin-org/wpl/includes/Message.php(590): Message->parseText()
#5 /usr/www/users/nicollb/famvin-org/wpl/includes/Message.php(669): Message->toString()
#6 /usr/www/users/nicollb/famvin-org/wpl/includes/OutputPage.php(3605): Message->parseAsBlock()
#7 /usr/www/users/nicollb/famvin-org/wpl/includes/OutputPage.php(2167): OutputPage->addWikiMsgArray()
#8 /usr/www/users/nicollb/famvin-org/wpl/includes/Exception.php(335): OutputPage->showErrorPage()
#9 /usr/www/users/nicollb/famvin-org/wpl/includes/Exception.php(367): ErrorPageError->report()
#10 /usr/www/users/nicollb/famvin-org/wpl/includes/Exception.php(606): BadTitleError->report()
#11 /usr/www/users/nicollb/famvin-org/wpl/includes/Exception.php(678): MWExceptionHandler::report()
#12 /usr/www/users/nicollb/famvin-org/wpl/includes/Wiki.php(470): MWExceptionHandler::handle()
#13 /usr/www/users/nicollb/famvin-org/wpl/index.php(49): MediaWiki->run()
#14 {main}