The January edition of CIO had another article on the need for
companies to proactively manage and be able to access the content of
the e-mails flowing in and out of their servers. In
addition to just creating storage repositories companies have install
tools allowing them to index and access those messages in a timely
The article also talks about how companies are installing tools to allow them to constantly monitor compliance with e-mail usage rules (and other compliance issues) and then notify compliance officers when policies are violated.
Good read to learn more about some of the issues involved and how to deal with them.
CIO - "Message Therapy"