2+ nameservers sharing 1 ip?

[tc lewis]

the manage client interface (action=manage_nameserversmeservers) doesn't
seem to allow me to create 2 nameservers with the same ip:

Unable to create nameserver: Registry error, nameserver creation failed
[Attribute value not unique]

is there any technical reason for this?  is this just an extra step of
user error prevention?  any way to get around it?

-tcl.