Geocoder.cache returning cache store instead of Geocoder::Cache instance.

Running *Geocoder.cache.expire(:all)* with a Redis cache store results in the following error (Rails 3.2.12):

    ArgumentError: wrong number of arguments (1 for 2)
        from /Users/.../gems/redis-3.0.2/lib/redis.rb:301:in `expire'

Geocoder is calling the *expire* method directly on the Redis client, instead of the expire method in Geocoder::Cache.