I am able to generate "clntsrv.iso" image for the clntsrv application given in l4/pkg/examples directory.

But when i execute in qemu, i get 

 BOOTFS: [1418000-154fef5] [C:503000] l4re
 BOOTFS: [1550000-162e6e6] [C:504000] clntsrv-client
 BOOTFS: [162f000-1714483] [C:505000] clntsrv-server
No fpage received
MOE: cmdline: moe --init=rom/clntsrv-server
MOE: Starting: rom/clntsrv-server 
MOE: loading 'rom/clntsrv-server'
Could not register my service, is there a 'calc_server' in the caps table?
MOE: task 1565571 exited with 1

Please help...

Gayathri