404 Environment groups after upgrade to gitlab 9.0

Summary

After updating to gitlab 9.0.0 I cannot access my environments anymore.
It produces 404 - The page you're looking for could not be found.

Steps to reproduce

The problem is with groups named with a . in the name (release-v0.x.x).
This is somehow only a problem on the parent group.

My environments are generated with gitlab-ci:

.deploy: &deploy
  stage: deploy
  script:
    - mvn wildfly:deploy-only -P ${DEPLOY_PROFILE}
  only:
    - tags
  when: on_success
  environment:
    name: "release-$CI_BUILD_REF_NAME/Produktion/$NAME"

.staging: &staging
  <<: *deploy
  only:
    - /^release-.*$/
  environment:
    name: "$CI_BUILD_REF_NAME/Staging/$NAME"

Deploy dev:
  stage: deploy
  script:
    - mvn wildfly:deploy-only -P wildfly-dev,localdev 
  only:
    - master
  when: on_success
  environment:
    name: "Dev"

Deploy Staging XXX:
  <<: *staging
  variables:
    DEPLOY_PROFILE: wildfly-staging-xxx
    NAME: "XXX"

What is the current bug behavior?

I have groups for every single release, which contains several environments.

release-v0.18.0/test/a  
release-v0.18.0/prod/a

When clicking on a group, I get a 404 error.

What is the expected correct behavior?

Enter the environment groups and let me see my environments

Relevant logs and/or screenshots

Screenshot_from_2017-03-23_09-36-06

Results of GitLab environment info

System information
System:		
Current User:	git
Using RVM:	no
Ruby Version:	2.3.3p222
Gem Version:	2.6.6
Bundler Version:1.13.7
Rake Version:	10.5.0
Redis Version:	3.2.5
Git Version:	2.10.2
Sidekiq Version:4.2.7

GitLab information
Version:	9.0.0
Revision:	cf020e6
Directory:	/opt/gitlab/embedded/service/gitlab-rails
DB Adapter:	postgresql
URL:		https://git.url
HTTP Clone URL:	https://git.url/some-group/some-project.git
SSH Clone URL:	git@git.url:some-group/some-project.git
Using LDAP:	no
Using Omniauth:	no

GitLab Shell
Version:	5.0.0
Repository storage paths:
- default: 	/var/opt/gitlab/git-data/repositories
Hooks:		/opt/gitlab/embedded/service/gitlab-shell/hooks/
Git:		/opt/gitlab/embedded/bin/git

Results of GitLab application Check

Checking GitLab Shell ...

GitLab Shell version >= 5.0.0 ? ... OK (5.0.0)
Repo base directory exists?
default... yes
Repo storage directories are symlinks?
default... no
Repo paths owned by git:git?
default... yes
Repo paths access is drwxrws---?
default... yes
hooks directories in repos are links: ... 
5/2 ... ok
5/3 ... ok
7/11 ... ok
7/12 ... ok
5/13 ... ok
5/15 ... ok
5/16 ... ok
29/17 ... ok
5/19 ... ok
29/20 ... ok
32/21 ... ok
29/22 ... ok
19/23 ... ok
5/24 ... ok
38/25 ... ok
5/26 ... ok
32/28 ... ok
5/29 ... ok
32/30 ... ok
5/31 ... repository is empty
9/32 ... repository is empty
5/33 ... ok
5/34 ... ok
5/35 ... ok
41/37 ... ok
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Check GitLab API access: OK
Access to /var/opt/gitlab/.ssh/authorized_keys: OK
Send ping to redis server: OK
gitlab-shell self-check successful

Checking GitLab Shell ... Finished

Checking Sidekiq ...

Running? ... yes
Number of Sidekiq processes ... 1

Checking Sidekiq ... Finished

Checking Reply by email ...

Reply by email is disabled in config/gitlab.yml

Checking Reply by email ... Finished

Checking LDAP ...

LDAP is disabled in config/gitlab.yml

Checking LDAP ... Finished

Checking GitLab ...

Git configured with autocrlf=input? ... yes
Database config exists? ... yes
All migrations up? ... yes
Database contains orphaned GroupMembers? ... no
GitLab config exists? ... yes
GitLab config outdated? ... no
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory setup correctly? ... yes
Init script exists? ... skipped (omnibus-gitlab has no init script)
Init script up-to-date? ... skipped (omnibus-gitlab has no init script)
projects have namespace: ... 
5/2 ... yes
5/3 ... yes
7/11 ... yes
7/12 ... yes
5/13 ... yes
5/15 ... yes
5/16 ... yes
29/17 ... yes
5/19 ... yes
29/20 ... yes
32/21 ... yes
29/22 ... yes
19/23 ... yes
5/24 ... yes
38/25 ... yes
5/26 ... yes
32/28 ... yes
5/29 ... yes
32/30 ... yes
5/31 ... yes
9/32 ... yes
5/33 ... yes
5/34 ... yes
5/35 ... yes
41/37 ... yes
Redis version >= 2.8.0? ... yes
Ruby version >= 2.1.0 ? ... yes (2.3.3)
Your git bin path is "/opt/gitlab/embedded/bin/git"
Git version >= 2.7.3 ? ... yes (2.10.2)
Active users: 34

Checking GitLab ... Finished