Redmine

Currently we have the below version installed and as per the revision mentioned on other similar issues - r10073 which has addressed this issue already part of older redmine releases.
But this feature of grouping by custom fields does not seems to be working on the below version. Let us know the solution.

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Environment:
Redmine version 2.5.2.stable
Ruby version 1.9.3-p545 (2014-02-24) [i386-mingw32]
Rails version 3.2.19
Environment production
Database adapter PostgreSQL
SCM:
Subversion 1.8.10
Git 1.9.2
Filesystem
Redmine plugins:
no plugin installed