Updatefehler: Fatal error: SQLSTATE[42000]: Syntax error or access violation: 1115 Unknown character set: 'utf8mb4'

Fatal error: SQLSTATE[42000]: Syntax error or access violation: 1115 Unknown character set: 'utf8mb4'
Information:
id: 9c224c26386b957f5d11e893c50e8b9c3e3a2f65
error message: SQLSTATE[42000]: Syntax error or access violation: 1115 Unknown character set: 'utf8mb4'
error code: 42000
sql type: wcf\system\database\MySQLDatabase
sql error: Unknown character set: 'utf8mb4'
sql error number: 42000
sql version: 5.1.73-log
sql query: ALTER TABLE wcf13_acp_session CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci
file: /cwalz.de/wcf/lib/system/database/Database.class.php (231)
php version: 7.0.11
wcf version: 2.1.12 (Typhoon)
date: Sat, 04 Feb 2017 05:44:18 +0000
request: /acp/index.php?install-package/&
referer: https://cwalz.de/acp/index.php?package-update/&s
Stacktrace:
#0 /cwalz.de/wcf/acp/update_com.woltlab.wcf_3.0_pre_sql.php(5): wcf\system\database\Database->prepareStatement('ALTER TABLE wcf...')
#1 /cwalz.de/wcf/lib/system/package/plugin/ScriptPackageInstallationPlugin.class.php(69): include('/var/www/virtua...')
#2 /cwalz.de/wcf/lib/system/package/plugin/ScriptPackageInstallationPlugin.class.php(47): wcf\system\package\plugin\ScriptPackageInstallationPlugin->run('/var/www/virtua...')
#3 /cwalz.de/wcf/lib/system/package/plugin/AbstractPackageInstallationPlugin.class.php(72): wcf\system\package\plugin\ScriptPackageInstallationPlugin->install()
#4 /cwalz.de/wcf/lib/system/package/PackageInstallationDispatcher.class.php(571): wcf\system\package\plugin\AbstractPackageInstallationPlugin->update()
#5 /cwalz.de/wcf/lib/system/package/PackageInstallationDispatcher.class.php(139): wcf\system\package\PackageInstallationDispatcher->executePIP(Array)
#6 /cwalz.de/wcf/lib/acp/action/InstallPackageAction.class.php(73): wcf\system\package\PackageInstallationDispatcher->install('97fa5cd6')
#7 /cwalz.de/wcf/lib/action/AbstractDialogAction.class.php(70): wcf\acp\action\InstallPackageAction->stepInstall()
#8 /cwalz.de/wcf/lib/action/AbstractAction.class.php(49): wcf\action\AbstractDialogAction->execute()
#9 /cwalz.de/wcf/lib/system/request/Request.class.php(58): wcf\action\AbstractAction->__run()
#10 /cwalz.de/wcf/lib/system/request/RequestHandler.class.php(139): wcf\system\request\Request->execute()
#11 /cwalz.de/acp/index.php(10): wcf\system\request\RequestHandler->handle('wbb', true)
#12 {main}