problem with enbd init on standby

Hi all,
my standby config is between host A and host B. I'm using raid1 on A 
consisting of a local device and a nbd device from standby. After 
switching over to B, I use B's local devices and put them into a raid1. 
The intention is, to get it synchronized to the A's nbds again. However 
when starting the server on A and client on B I get the log looks like this:
enbd-client 12193: client says target 0 is mks:1130
enbd-client 12193: <# 454> set_channels client sees target 0 is mks:1130
enbd-client 12193: <# 454> set_channels client sees target 1 is mks:1130
enbd-client 12193: <# 454> set_channels client sees target 2 is mks:1130
enbd-client 12193: <# 499> set_servername client says host name 4 is 
/dev/nda
enbd-client 12193: <# 840> cmdline client says device name is /dev/nda
enbd-client 12193: <#4178> main Created NBD ioctl buffer size 263144
enbd-client 12193: <#3586> open_special client (-1) tries to open device 
/dev/nda
enbd-client 12193: client (-1) opened device /dev/nda
enbd-client 12193: client (-1) manager opened NBD device /dev/nda (2b00)
enbd-client 12193: client (-1) set kernel bdflush sync boundary to 80% 
from 0%
enbd-client 12193: client (-1) set kernel bdflush async boundary to 25% 
from 1075070048%
enbd-client 12193: <#4222> main Set pid file /var/run/enbd-client-8.pid d
enbd-client 12193: client (-1) manager detaches from shell
enbd-client 12193: <#4230> main client manager parent 12193 tries to die
linscm03:/usr/local/src/nbd-2.4.32 # nbd/pidfile 12195: <# 145> 
lockpidfile returning err 0 for lock attempt
enbd-client 12195: client (-1) manager made pidfile 
/var/run/enbd-client-8.pid with pid 12195
nbd/time 12195: <#  64> mygettimeofday time was 0+0E-6 s and is 
1123763469+794524E-6 s
enbd-client 12195: <#4277> main client (-1) manager started new process 
group 12195
enbd-client 12195: <#4303> main client (-1) manager sees target 0 is 
mks:1130(1130)
enbd-client 12195: <#4303> main client (-1) manager sees target 1 is 
mks:1130(1130)
enbd-client 12195: <#4303> main client (-1) manager sees target 2 is 
mks:1130(1130)
enbd-client 12195: <#4316> main client (-1) manager sees 1 distinct targets
enbd-client 12195: <#4334> main client (-1) manager tries target mks:1130
enbd-client 12195: client (-1) starts introduction sequence on mks:1130
enbd-client 12195: <#2627> introduction client (-1) joins inits pgrp
enbd-client 12195: <#2632> introduction client (-1) resets sighandlers
enbd-client 12195: <#2638> introduction client (-1) has initial socket -1
enbd-client 12195: <#2671> introduction client (-1) opened socket 5 to 
mks:1130
enbd-client 12195: <#2375> expect client (-1) starts expect sequence intro
enbd-client 12195: <#2401> expect try looking for read command Helo
enbd-client 12195: <#2242> command Search for key Helo
enbd-client 12195: <#2247> command Fetch 11 more bytes from net to total 11
enbd-client 12195: <#2258> command buffer [helo]
enbd-client 12195: <#2275> command found Helo
enbd-client 12195: <#2290> command Fetch 5 more bytes from net to total 16
enbd-client 12195: <#2424> expect command Helo received
enbd-client 12195: <#2453> expect client has read helo nbd-client
enbd-client 12195: <#2456> expect mark Helo as actioned
enbd-client 12195: <#2327> drop shift buff 5 left to total 11
enbd-client 12195: <#2464> expect client (-1) returns with Helo from expect
enbd-client 12195: <#2751> introduction client (-1) introduction begins
enbd-client 12195: <#2327> drop shift buff 11 left to total 0
enbd-client 12195: <#2401> expect try looking for read command pass
enbd-client 12195: <#2242> command Search for key pass
enbd-client 12195: <#2247> command Fetch 9 more bytes from net to total 9
enbd-client 12195: <#2258> command buffer [pass]
enbd-client 12195: <#2275> command found pass
enbd-client 12195: <#2290> command Fetch 5 more bytes from net to total 14
enbd-client 12195: <#2424> expect command pass received
enbd-client 12195: <#2453> expect client has read pass NBDMAGIC
enbd-client 12195: <#2456> expect mark pass as actioned
enbd-client 12195: <#2327> drop shift buff 5 left to total 9
enbd-client 12195: <#2464> expect client (-1) returns with pass from expect
enbd-client 12195: <#2763> introduction client (-1) read passwd 
[NBDMAGIC] ok from mks:1130
enbd-client 12195: <#2401> expect try looking for read command mgck
enbd-client 12195: <#2242> command Search for key mgck
enbd-client 12195: <#2247> command Fetch 19 more bytes from net to total 19
enbd-client 12195: <#2258> command buffer [mgck]
enbd-client 12195: <#2275> command found mgck
enbd-client 12195: <#2290> command Fetch 5 more bytes from net to total 24
enbd-client 12195: <#2424> expect command mgck received
enbd-client 12195: <#2453> expect client has read mgck 0x0000420281861253
enbd-client 12195: <#2456> expect mark mgck as actioned
enbd-client 12195: <#2464> expect client (-1) returns with mgck from expect
enbd-client 12195: <#2785> introduction client (-1) got cliserv magic ok
enbd-client 12195: <#2405> expect try looking for write command rdev
enbd-client 12195: <#2409> expect result from looking for write command 
rdev is 4
enbd-client 12195: <#2427> expect writing data for command rdev
enbd-client 12195: <#2434> expect client (-1) suggested rdev 2b00
  to server
enbd-client 12195: <#2437> expect have 0 after offset 4, need 5 more in buf
enbd-client 12195: <#2343> fill Fetch 1 more bytes from net to total 5
enbd-client 12195: <#2343> fill Fetch 1 more bytes from net to total 6
enbd-client 12195: <#2343> fill Fetch 1 more bytes from net to total 7
enbd-client 12195: <#2448> expect skipped 6B@4B to EOL
enbd-client 12195: <#2791> introduction client (-1) got rdev 0x2b00 ok
enbd-client 12195: client (-1) got size 42949672960
enbd-client 12195: client (-1) got signature [8], had []
enbd-client 12195: <#2881> introduction client (-1) received remote 
resource ro flags 0
enbd-client 12195: <#2899> introduction client (-1) negotiated device ro 
flags 0
enbd-client 12195: <#2405> expect try looking for write command bksz
enbd-client 12195: <#2409> expect result from looking for write command 
bksz is 4
enbd-client 12195: <#2427> expect writing data for command bksz
enbd-client 12195: <#2434> expect client (-1) suggested bksz 1024
  to server
enbd-client 12195: <#2437> expect have 0 after offset 4, need 5 more in buf
enbd-client 12195: <#2366> fill Warning - read only 0/1B on descriptor 
5: Invalid argument
enbd-client 12195: <#2448> expect skipped 11B@4B to EOL
enbd-client 12195: <#2451> expect Warning - client read half line <bksz 
13107rqto >
enbd-client 12195: <#2824> introduction client (-1) suggested blksize 
1024 to server
enbd-client 12195: <#2835> introduction client (-1) received suggestion 
blksize 13107
enbd-client 12195: client (-1) negotiated blksize 13107
enbd-client 12195: <#2405> expect try looking for write command rqto
enbd-client 12195: <#2272> command key rqto not found
enbd-client 12195: <#2409> expect result from looking for write command 
rqto is -1
enbd-client 12195: <#2541> expect client (-1) fails in expect sequence
enbd-client 12195: <#2999> introduction client (-1) introduction 
sequence ends FAIL
 From A to B everything works fine.
regards Uwe