Internal error

[ZgVZyTIvBPZAz3-G@QgjtQAAAAM] /cbg/index.php?title=Contact&oldid=3492 Error from line 85 of /var/www/html/prod/cbg/extensions/Maps/includes/Maps_Mapper.php: Call to undefined function wfMsg()

Backtrace:

#0 /var/www/html/prod/cbg/extensions/Maps/includes/parserHooks/Maps_DisplayPoint.php(56): MapsMapper::getCommonParameters()
#1 /var/www/html/prod/cbg/extensions/Validator/includes/ParserHook.php(366): MapsDisplayPoint->getParameterInfo(integer)
#2 /var/www/html/prod/cbg/extensions/Validator/includes/ParserHook.php(295): ParserHook->validateAndRender(array, integer)
#3 /var/www/html/prod/cbg/extensions/Validator/includes/ParserHook.php(337): ParserHook->renderFunction(Parser, string, string)
#4 /var/www/html/prod/cbg/extensions/Validator/includes/ParserHook.php(636): ParserHook->renderFunctionObj(Parser, PPFrame_DOM, array)
#5 /var/www/html/prod/cbg/includes/parser/Parser.php(3426): ParserHookCaller->runFunctionHookObj(Parser, PPFrame_DOM, array)
#6 /var/www/html/prod/cbg/includes/parser/Parser.php(3127): Parser->callParserFunction(PPFrame_DOM, string, array)
#7 /var/www/html/prod/cbg/includes/parser/Preprocessor_DOM.php(1277): Parser->braceSubstitution(array, PPFrame_DOM)
#8 /var/www/html/prod/cbg/includes/parser/Parser.php(2942): PPFrame_DOM->expand(DOMElement, integer)
#9 /var/www/html/prod/cbg/includes/parser/Parser.php(1293): Parser->replaceVariables(string)
#10 /var/www/html/prod/cbg/includes/parser/Parser.php(443): Parser->internalParse(string)
#11 /var/www/html/prod/cbg/includes/content/WikitextContent.php(323): Parser->parse(string, Title, ParserOptions, boolean, boolean, integer)
#12 /var/www/html/prod/cbg/includes/content/AbstractContent.php(516): WikitextContent->fillParserOutput(Title, integer, ParserOptions, boolean, ParserOutput)
#13 /var/www/html/prod/cbg/includes/poolcounter/PoolWorkArticleView.php(144): AbstractContent->getParserOutput(Title, integer, ParserOptions)
#14 /var/www/html/prod/cbg/includes/poolcounter/PoolCounterWork.php(123): PoolWorkArticleView->doWork()
#15 /var/www/html/prod/cbg/includes/page/Article.php(604): PoolCounterWork->execute()
#16 /var/www/html/prod/cbg/includes/actions/ViewAction.php(68): Article->view()
#17 /var/www/html/prod/cbg/includes/MediaWiki.php(500): ViewAction->show()
#18 /var/www/html/prod/cbg/includes/MediaWiki.php(294): MediaWiki->performAction(Article, Title)
#19 /var/www/html/prod/cbg/includes/MediaWiki.php(818): MediaWiki->performRequest()
#20 /var/www/html/prod/cbg/includes/MediaWiki.php(524): MediaWiki->main()
#21 /var/www/html/prod/cbg/index.php(42): MediaWiki->run()
#22 {main}