New features in this version:

* The system is upgraded to Rails 0.14.2
* The default session store now is ActiveRecord store
* There is no usage of DRb anymore. The drb_services.rb file is removed.
* There is a new caching algorithm implemented. Header fields of the
messages are cached in the local database
* There is a new "debug_imap" option in the configuration file.
Hopefully it will help to track some strange problems with the Net::IMAP
implementation
* Fixes of some encoding issues
* Fixes of issues with attachments