[TYPO3-seminars] Typo3 6.2 Error: onetimeaccount - oelib - seminars

[Ingo Lacheiner]

Hallo!

I´m using Seminars on Typo3 6.2.6. 
Seminars 0.9.95
oelib 0.7.76
onetimeaccount 0.9.51 

Provider: jweiland.net

Everything works fine till the last step in registration. Then the following error occurs:

Fatal error: Call to private Tx_Oelib_MailerFactory::__construct() from context 'TYPO3\CMS\Core\Utility\GeneralUtility' in /kunden/275685_70794/rp-hosting/11955/61956/typo3cms/typo3_src-6.2.3/typo3/sysext/core/Classes/Utility/GeneralUtility.php on line 4365 

Did someone geht the same problem?
The Organizer have a Mail-Adress, also the Trainer.

Thank you for your help.

Ingo Lacheiner