According to wanghui's comment, this issue was fixed in version:
rhev-hypervisor6-6.5-20131017.0.iso
ovirt-node-3.0.1-4.el6.noarch
but the item of nfs location in kdump page still could accept ipv6 address in version:
ovirt-node-iso-3.0.3-1.1.fc19.iso
ovirt-node-3.0.3-1.fc19.noarch