Once a node has been registered to a domain, you can't update it and
assign it to a new domain.  I had the need to remove a node from the
standard domain and establish it in a seperate domain.  What I ended up
doing was doing an export, renaming the node in case I had a problem,
re-registering the node in the new domain, and then doing an import.
This worked fine for me.  The only issue that I had was that I also
created a seperate storage pool hierahcy for the new domain and I had
no way of copying or moving the copy storage pool data.  I ended up
just recreating the copy storage pool data.

Elvin