cannot save new disk volumes for nodes

Affects at least Fuel 6.0 and 6.1
ISO 6.0 GA
VERSION:
  feature_groups:
    - mirantis
    - experimental
  production: "docker"
  release: "6.0"
  api: "1.0"
  build_number: "58"
  build_id: "2014-12-26_14-25-46"
  astute_sha: "16b252d93be6aaa73030b8100cf8c5ca6a970a91"
  fuellib_sha: "fde8ba5e11a1acaf819d402c645c731af450aff0"
  ostf_sha: "a9afb68710d809570460c29d6c3293219d3624d4"
  nailgun_sha: "5f91157daa6798ff522ca9f6d34e7e135f150a90"
  fuelmain_sha: "81d38d6f2903b5a8b4bee79ca45a54b76c1361b8"

ISO 6.1
"build_id": "2015-04-21_22-54-31",
"build_number": "337",
"api": "1.0",
"fuel-library_sha": "af4eee78a4dd6e6606079f5515bac91c45b04114",
"nailgun_sha": "3928c5aee6e7aabad37cf0665acc6790ef220141",
"feature_groups":
["mirantis"],
"openstack_version": "2014.2-6.1",
"production": "docker",
"python-fuelclient_sha": "08640730176591a3818f24e75b710f8c95846e6e",
"astute_sha": "bf1751a4fe0d912325e3b4af629126a59c1b2b51",
"fuel-ostf_sha": "df8db1f48f03b18126ce5ec65317a1eb83a5a95f",
"release": "6.1",
"fuelmain_sha": "aad0a7ad97a5660f5d53fa830b168d36fa9694eb"

Desc: new disk volumes doesn't appear when they are added and saved.

Steps to reproduce:
1) Create a cluster with Ceph for Glance.
2) Add a controller node (an only volume called 'os' required for a controller w/o Swift enabled).
3) Go to the Settings tab and uncheck the Ceph for Glance checkbox. (This enables Swift on controllers, so an additional volume called 'image' requires to be allocated)
4) Go to the node disk settings.
5) No disk partitions appear (see attached screenshot). It's because a JS code cannot find a volume called 'image'.
6) Click "Load Defaults". Disk partitions appear.
7) Click "Save". A PUT request ends with the 200 http code, but returns a wrong data (two volumes in a request, and only one in a response). http://paste.openstack.org/show/212964/

Workaround:
Delete a node from a cluster and add it again.

This behavior should be documented at least.