helion:~ gavin$ sudo gem install mofo
WARNING: Improper use of the sudo command could lead to data loss
or the deletion of important system files. Please double-check your
typing when using sudo. Type "man sudo" for more information.
To proceed, enter your password, or type Ctrl-C to abort.
MacOS X 10.4.9 added the prompt ?
I seem to remember this prompt only showed up once, and it was right after I installed 10.4.9. I assume it was a replacement for (or supplement to?) the older three-point message about being responsible as a priviledged user.