"SE Linux" is all about security:
Taking advantage of SE Linux (or, alternatively, disabling it) is largely a matter of configuration (for example, setting "policies").
The link above should have plenty of information for you.
'Hope that helps .. PSM
PS:
This article (by Mick Bauer, of Linux Journal's great monthly security column, "The Paranoid Penguin") is also a great introduction:
http://www.linuxjournal.com/article/9500
