resync problem for git

[mountainpaul@…]

git version 1.5.6.5 trac-admin 0.12 trac-git commit ​http://github.com/hvr/trac-git-plugin/commit/672da40cca475e493861bb93ed25f9a2fd06b771

I try to do the following: from the tracs project_env I run trac-admin . then repository resync * This results in

TypeError: 'NoneType' object is unsubscriptable

Relevant trac.ini sections

[git]
## let Trac cache meta-data via CachedRepository wrapper; default: false
cached_repository = false

## disable automatic garbage collection for in-memory commit-tree cache; default: false
persistent_cache = false

## length revision sha-sums should be tried to be abbreviated to (must be >= 4 and <= 40); default: 7
shortrev_len = 7

## (0.12.0.3+) minimum length for which hex-strings will be interpreted as commit ids in wiki context; default: 40
wiki_shortrev_len = 40

## executable file name (in case of doubt use absolute path!) of git binary; default: 'git'
git_bin = /usr/bin/git

## (0.12.0.5+) define charset encoding of paths stored within git repository; default: 'utf-8'
git_fs_encoding = utf-8

## (0.12.0.3+) enable reverse mapping of git email addresses to trac user ids; default: false
trac_user_rlookup = false

## (0.12.0.3+) use git-committer id instead of git-author id as changeset owner; default: true
use_committer_id = true

## (0.12.0.3+) use git-committer timestamp instead of git-author timestamp as changeset time; default: true
use_committer_time = true

[trac]
repository_dir = /var/git-repos/hearth.git
repository_type = git

[components]

tracext.git.* = enabled 

[anonymous]

Resolved: The system was reading the global(python 2.5 site-packages) tracext (version .11), instead of the local one (version for .12).

Ideally, it seems a plugin from the local env, should be loaded instead of one from the global env if it exists.