Running unity-app headless on linux - SIGSEGV

We are trying to run a little unity server on a linux machine Console:

jklaus@spielVI:~/loadtest$ xvfb-run --auto-servernum --server-args='-screen 0 640x480x24:32' ./test64d -batchmode -logfile output64d.txt

Set current directory to /home/jklaus/loadtest

Found path: /home/jklaus/loadtest/test64d

Aborted

there is a SIGSEGV, the log shows following

 Stacktrace:
 
 
 Native stacktrace:
 
     /home/jklaus/loadtest/test64d_Data/Mono/x86_64/libmono.so(+0x8fc73) [0x7f39d75e9c73]
     /home/jklaus/loadtest/test64d_Data/Mono/x86_64/libmono.so(+0xcfc9d) [0x7f39d7629c9d]
     /lib/x86_64-linux-gnu/libpthread.so.0(+0xf030) [0x7f39d97e8030]
     ./test64d() [0xa616c7]
     ./test64d() [0xa4ba9a]
     ./test64d() [0xa66ae3]
     /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xfd) [0x7f39d8ac6ead]
     ./test64d() [0x41f519]
 
 Debug info from gdb:
 
 
 =================================================================
 Got a SIGSEGV while executing native code. This usually indicates
 a fatal error in the mono runtime or one of the native libraries 
 used by your application.
 =================================================================
 
 

we tried it in 32 and 64 bit mode, development and production mode. This error occures on Gentoo, Debian and Suse. Only on Ubuntu 12.04 we got it to run. What do we wrong ?