Realm not being used for password hash?

[james]

As a test I set the password of my user (james) through the account settings on trac to 'helloworld'. In the database this set the password to ':f4a19cee25aae3fe30d7a319fb7c5144'

I can reproduce this hash like so:

echo -n james::helloworld | md5
f4a19cee25aae3fe30d7a319fb7c5144

However I thought trac would use the realm set in trac.ini to essentially do this:

echo -n james:TracDB:helloworld | md5
8c41eb73b4e4d22f173b2a302d52dfdd

I'm obviously missing something, can anyone see what is it? Here are my account manager settings:

[account-manager]
account_changes_notify_addresses =
hash_method = HtDigestHashMethod
db_htdigest_realm = TracDB
password_store = SessionStore
login_attempt_max_count = 3
user_lock_time = 30
user_lock_time_progression = 1

[components]
acct_mgr.guard.accountguard = enabled
acct_mgr.admin.accountmanageradminpages = enabled
acct_mgr.api.accountmanager = enabled
acct_mgr.db.sessionstore = enabled
acct_mgr.htfile.htdigeststore = enabled
acct_mgr.notification.accountchangelistener = enabled
acct_mgr.notification.accountchangenotificationadminpage = enabled
acct_mgr.pwhash.htdigesthashmethod = enabled
acct_mgr.web_ui.accountmodule = enabled
acct_mgr.web_ui.emailverificationmodule = enabled
acct_mgr.web_ui.loginmodule = enabled
acct_mgr.web_ui.registrationmodule = disabled
acct_mgr.web_ui.resetpwstore = disabled
trac.web.auth.loginmodule = disabled
tracopt.versioncontrol.git.* = enabled

[Steffen Hoffmann]

reformatting for readability