Fatal error: PHP notice in file /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/session/CookieSessionFactory.class.php (121): Use of undefined constant COOKIE_PREFIX - assumed 'COOKIE_PREFIX'

Information:

error message: PHP notice in file /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/session/CookieSessionFactory.class.php (121): Use of undefined constant COOKIE_PREFIX - assumed 'COOKIE_PREFIX'
error code: 0
file: /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/WCF.class.php (255)
php version: 5.4.39
wcf version: 1.0.11 pl 4 (Horizon)
date: Wed, 27 May 2015 17:34:56 +0000
request: /index.php?page=Thread&postID=250650
referer:

Stacktrace:

#0 /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/session/CookieSessionFactory.class.php(121): WCF::handleError(8, 'Use of undefine...', '/homepages/34/d...', 121, Array)
#1 /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/session/SessionFactory.class.php(61): CookieSessionFactory->readSessionID()
#2 /homepages/34/d354817557/htdocs/dscboard/lib/system/WBBCore.class.php(201): SessionFactory->get()
#3 /homepages/34/d354817557/htdocs/dscboard/wcf/lib/system/WCF.class.php(91): WBBCore->initSession()
#4 /homepages/34/d354817557/htdocs/dscboard/global.php(18): WCF->__construct()
#5 /homepages/34/d354817557/htdocs/dscboard/index.php(7): require_once('/homepages/34/d...')
#6 {main}