MediaWiki internal error.

Original exception: exception 'MWException' with message 'Detected bug in an extension! Hook efGoogleAnalyticsHookText failed to return a value; should return true to continue hook processing or false to abort.' in /home/hugo/public_html/wiki/includes/Hooks.php:137
Stack trace:
#0 /home/hugo/public_html/wiki/includes/Skin.php(754): wfRunHooks('SkinAfterBottom...', Array)
#1 /home/hugo/public_html/wiki/includes/SkinTemplate.php(404): Skin->bottomScripts()
#2 /home/hugo/public_html/wiki/includes/OutputPage.php(821): SkinTemplate->outputPage(Object(OutputPage))
#3 /home/hugo/public_html/wiki/includes/Wiki.php(337): OutputPage->output()
#4 /home/hugo/public_html/wiki/index.php(94): MediaWiki->finalCleanup(Array, Object(OutputPage))
#5 {main}

Exception caught inside exception handler: exception 'MWException' with message 'Detected bug in an extension! Hook efGoogleAnalyticsHookText failed to return a value; should return true to continue hook processing or false to abort.' in /home/hugo/public_html/wiki/includes/Hooks.php:137
Stack trace:
#0 /home/hugo/public_html/wiki/includes/Skin.php(754): wfRunHooks('SkinAfterBottom...', Array)
#1 /home/hugo/public_html/wiki/includes/SkinTemplate.php(404): Skin->bottomScripts()
#2 /home/hugo/public_html/wiki/includes/OutputPage.php(821): SkinTemplate->outputPage(Object(OutputPage))
#3 /home/hugo/public_html/wiki/includes/Exception.php(150): OutputPage->output()
#4 /home/hugo/public_html/wiki/includes/Exception.php(174): MWException->reportHTML()
#5 /home/hugo/public_html/wiki/includes/Exception.php(260): MWException->report()
#6 /home/hugo/public_html/wiki/includes/Exception.php(294): wfReportException(Object(MWException))
#7 [internal function]: wfExceptionHandler(Object(MWException))
#8 {main}