Installation:
perl Makefile.PL
make
sudo make install

This version of Apache2::AuthTicketLDAP overloads several methods from
Apache::AuthTicket, including:

===============================================================================
Plan to submit upstream
===============================================================================
dbi_connect()
a) passwordless local connections
b) AutoCommit via TicketDBAutoCommit option
c) a couple of Informix-specific options (ISOLATION and LOCK MODE)

_update_ticket_timestamp()
a) TicketThreshold: Only update the database when a ticket timestamp is at
least X seconds old. Reduces database updates.

===============================================================================
Needs some work to support configuration, but could be submitted upstream
===============================================================================
hash_for()
a) Use Digest::SHA instead of MD5

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Will not submit upstream due to using cache
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is_hash_valid()
a) Use a SQL SELECT statement result cache

fetch_secret()
a) Use a SQL SELECT statement result cache
b) Change DESC LIMIT 1 to SELECT FIRST 1. This is an Informix-ism.
c) Don't listen to SQL::Abstract's quoting of the version number, which
Informix doesn't like.
d) FIXME: Informixisms should be ifdef'd for Driver eq Informix. Also, SELECT
FIRST is only supported in Informix 10+

check_credentials()
a) Use LDAP
b) Use LDAP Entry cache