error: apple device / z-push /calendar sync

[remmedia]

Ping of calendar sync throws error 500 about 3 of 4 times

log file:

[Wed Jan 22 17:31:53 2014] [warn] [client X.X.X.X] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server
[Wed Jan 22 17:31:53 2014] [error] [client X.X.X.X] Premature end of script headers: index.php

[remmedia]

Seams to be a Problem with receiving ping for push from device

[webwolfi]

which apple device do you use?