zypper does not add lock for package in repository

felipe@suse-amd:~> sudo zypper lr | grep -i kde
1  | KDE3_OBS                   | KDE3_OBS                        | No      | No
13 | KDE3_backports             | KDE3_backports                  | Yes     | No
felipe@suse-amd:~> sudo zypper al -r KDE3_backports "k3b-lang"
Reading installed packages...
Specified lock has been successfully added.
felipe@suse-amd:~> sudo zypper ll
# | Name     | Type    | Repository
1 | k3b-lang | package | (any)

# ** with or without "QUOTES" does not matter

I had to manually edit /etc/zypp/locks and add:
repo: KDE3_backports to get it to work. bug??

Documentation differs from implementation, and your copy&pasted examples show it clearly. Sure, it’s a bug. Report it.