found the mistake!
The changes with FHEM 5.7 (2015.11.15) are responsible.
@ and % in notify are not longer allowed as well as %NAME, %EVENT.
Until now you has to use $NAME, $EVENT.
Example for a UniPi Relay DEV:
old: Relay5 { fhem "set relays0 PortA3 %" }
new: Relay5 { fhem "set relays0 PortA3 $EVENT" }