Fedora xen - Aug 2006 - Error 22 while installing NetBSD-DomU

Hey,

I found a nice manual for the installation for NetBSD.

http://wiki.xensource.com/xenwiki/NetBSDdomU

I downloaded the Kernel, gunziped etc. as mentionned.starting then, i
got this error:

Error: (22, ''Invalid argument'')

My config-file looks like this:

[root@neo xen]# more ork
kernel = "/root/netbsd-INSTALL_XENU"
memory = 256
name = "ork"
disk = [ ''file:/root/ork,xvda,w'' ]
ip = "10.0.0.6"
netmask = "255.0.0.0"
gateway = "10.0.0.3"

Any idea, why this happens, and what it is? selinux is disabled.

Thanks for your help.
Roger