[TYPO3-seminars] plugin.tx_seminars.attendancesPID - configuration check failure (Bug?)

[Kai Osthoff]

Hi Seminar-Users!
Hi Oliver!

Just update our seminars on our Webpage from seminars 0.9.1 -> 0.9.2. 
Now we get the configuration-check error for 
plugin.tx_seminars.attendancesPID

But why? in our template the seminars ts setup variable is configured 
with the correc pid.

Any ideas?

Greetings, Kai

P.S.: See the error at http://www.wltev.de/termine-seminare/