Error messages data is cached at $error_mail_analyzer_cache_dir directory.
IO to cache uses Tie::JournaledDir class via FML::Error::Cache.
FML::Error::Cache is a front end (adapter layer) for Tie::JournaledDir class. All IO should be done via methods provided by FML::Error::Cache.
author's homepage is www.fml.org/home/fukachan/.
Also, visit nuinui's world :) at www.nuinui.net.
For questions about FML, e-mail <fml-bugs@fml.org>.