I've never actually managed to do this and the following MSDN article seems
to suggest this is not possible:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/debug/base/even
t_logging_security.asp

In particular this line "The Security log is designed for use by the system.
However, users can read and clear the Security log..."

The "Manage auditing and security log" setting in the Policy Editor only
allows the reading and clearing of the security log - I'm not sure if there
is another setting in there that applies to this? I've only tried this on a
Windows XP dev box - not sure if there are different settings on a server
OS?