Unable to change hostnames of nodes being deployed by the rhel-osp-installer.

Issue

• Unable to change hostname of nodes being deployed by the RHEL OSP installer.
• Using subnets larger than /24.
• Logged error :

Started PUT "/api/v2/hosts/mac.cluster" for 10.0.39.101 at 2015-02-12 17:22:35 +0000
Processing by Api::V2::HostsController#update as JSON
  Parameters: {"name"=>"compute021.cluster", "apiv"=>"v2", "id"=>"mac.cluster", :host=>{"name"=>"compute021.cluster"}}
Authorized user admin(Admin User)
DNS PTR Records 10.0.39.136/mac.cluster already exists
Unprocessable entity Host::Managed (id: 93):
  Conflict DNS PTR Records 10.0.39.136/mac.cluster already exists

  Rendered api/v2/errors/unprocessable_entity.json.rabl within api/v2/layouts/error_layout (2.7ms)
Completed 422 Unprocessable Entity in 461ms (Views: 5.1ms | ActiveRecord: 35.7ms)

• Web user interface error :

Unable to save

Create DHCP Settings for compute021.cluster task failed with the following error: ERF12-6899 [ProxyAPI::ProxyException]: Unable to set DHCP entry ([RestClient::Conflict]: 409 Conflict) for proxy https://foreman01.cluster:8443/dhcp
Failed to perform rollback on Remove DHCP Settings for mac.cluster - ERF12-6899 [ProxyAPI::ProxyException]: Unable to set DHCP entry ([RestClient::BadRequest]: 400 Bad Request) for proxy https://foreman01.cluster:8443/dhcp