Comment 5 for bug 573391

I was able to get around it.

Looking for what the user snmp was doing I found

$~> ps auxf|grep [s]nmp
snmp 1129 0.0 0.0 10384 296 ? Ss 14:19 0:00 rpc.statd -L

After

$~> sudo /etc/init.d/statd stop

the process was gone and the user 'snmp' did no longer own any process and

$~> sudo dpkg --configure -a

completet without errors.