client (-1) cannot open NBD device /dev/nda or similar: No such file or directory

Hallo list!

I am trying to implement ENBD but I stuck at the moment when I want to connect from the client to the Server. Compiation of the source works fine, the modules are loading without a problem and I have no problem starting with the server. I would be -very- glad if someone could help! Nobody in the web seems to have my problem. I followed the instructions from: http://www.it.uc3m.es/~ptb/nbd/ but there has to be something missing. It is definitly not sudo (installed).

Environment:
Distri: Debian 4.0
Kernel: 2.6.18-6-686
ENBD: 2.4.35

PS: I know that client and server have the same hostname (clones).

Some output of the Systems:

== Server ==
debian32:~/enbd# lsmod | grep enbd
enbd_ioctl              5920  0
enbd                  583032  1 enbd_ioctl

debian32:~/enbd# ./enbd-server 4001 /dev/sda1
enbd-server[3843]: server: will open resources in mode linear
enbd-server[3843]: looking for blksize of /dev/sda1 with fstat...
enbd-server[3843]: blksize of /dev/sda1 is 4096                  
enbd-server[3843]: set final blksize of whole resource to 4096   
enbd-server[3843]: looking for size of fd 4 with seek SEEK_END...
enbd-server[3843]: set size of fd 4 to 98668544                  
enbd-server[3843]: server: set blksize to 4096.                  
enbd-server[3843]: size of exported file/device is 98668544B (24089 blocks)
enbd-server[3844]: server (-2) locked /var/state/enbd/server-1Bu49m.client_ips
enbd-server[3844]: server (-2) unlocked /var/state/enbd/server-1Bu49m.client_ips
enbd-server[3844]: server (-2) set new signal handlers                     

debian32:~/enbd# ps aux | grep enbd
root      3844  0.0  0.1   1844   664 pts/0    S    Nov03   0:00 ./enbd-server 4001 /dev/sda1
root      3872  0.0  0.1   2872   748 pts/0    S+   02:12   0:00 grep enbd

debian32:/usr/src/enbd-2.4.35# cat /proc/nbdinfo
Device a-p:     Closed

Also the test didn't work:
debian32:/usr/src/enbd-2.4.35# make test
enbd-server[5969]: server (-2) sighandler propagates signal 15
enbd-server[5969]: server (-2) sighandler terminates safely on signal 15
/tmp/enbd-server localhost/8:3033 /tmp/core0 /tmp/core1 -i NBDabcdefNBD -t 120 -b 1024 -l -w 500 -h 10000
enbd-server[6055]: server: will open resources in mode linear
enbd-server[6055]: looking for size of fd 4 with seek SEEK_END...
enbd-server[6055]: set size of fd 4 to 4194304
enbd-server[6055]: looking for size of fd 5 with seek SEEK_END...
enbd-server[6055]: set size of fd 5 to 4194304
enbd-server[6055]: size of exported file/device is 8388608B (8192 blocks)
enbd-server[6056]: server (-2) locked /var/state/enbd/server-NBDabcdefNBD.client_ips
enbd-server[6056]: server (-2) unlocked /var/state/enbd/server-NBDabcdefNBD.client_ips
enbd-server[6056]: server (-2) set new signal handlers
/tmp/enbd-client localhost:3033 -n 4 -b 1024 -i NBDabcdefNBD -t 120 -p 5 /dev/nda
enbd-client[6057]: enbd-client cmdline: #channels is 4
enbd-client[6057]: enbd-client cmdline: blksize is 1024
enbd-client[6057]: enbd-client cmdline: identifier is "NBDabcdefNBD"
enbd-client[6057]: enbd-client cmdline: negotiation timeout is 120
enbd-client[6057]: enbd-client cmdline: pulse intvl is 5
enbd-client[6057]: enbd-client #5757 main[0]: client (-1) cannot open NBD device /dev/nda or similar: No such file or directory
client not running
cannot open /dev/nda rw: Invalid argument
done


== Output of the Client ==

debian32:~/enbd# ls /dev/nda*
/dev/nda

debian32:~/enbd# ps aux | grep enbd
root      3790  0.0  0.1   2876   752 pts/0    S+   02:15   0:00 grep enbd

debian32:~/enbd# ./enbd-client 192.168.1.20:4001 -n 1  /dev/nda1
enbd-client[3788]: enbd-client cmdline: #channels is 1
enbd-client[3788]: enbd-client #5757 main[0]: client (-1) cannot open NBD device /dev/nda1 or similar: No such file or directory

I am thankful for every useful hint!

Greetinx

Volker