Launchd.plist quandry

Question

Per an earlier post, I finally got Snort® NIDS v2.8.3 compiled, installed, and configured on my Mac Pro running OS 10.5.4. It runs fine if invoked from the keyboard, in either daemon mode or non-daemon mode. I am having problems with launching it via launchd.plist, though, and am hoping that someone can look at my plist with a fresh set of eyes and perhaps be able to immediately tell me why snort isn't launching at computer bootup.
I want to launch an occurrence of Snort in daemon mode via launchd at bootup. The command that I use to invoke Snort in daemon mode from Terminal's command line is:
  /usr/local/bin/snort -DdevI -i en2 -l /var/log/snort/ -c /usr/local/snort-2.8.3/etc/snort.conf
This command works fine from Terminal's command line, and launches snort in daemon mode, when root.
My /Library/LaunchDaemons/snort.plist is:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN"
"http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>snort</string>
<key>ServiceDescription</key>
<string>launch SNORT® network intrusion detection system at bootup</string>
<key>ProgramArguments</key>
<array>
<string>/usr/local/bin/snort</string>
<string>-DdevI</string>
<string>-i en2</string>
<string>-l /var/log/snort/</string>
<string>-c /usr/local/snort-2.8.3/etc/snort.conf</string>
</array>
<key>RunAtLoad</key>
<true/>
</dict>
</plist> 
Other info of interest:
-rwxr-xr-x 1 root wheel /usr/local/bin/snort
-rw-r--r-- 1 root wheel /usr/local/snort-2.8.3/snort.plist
lrwxr-xr-x 1 root wheel /Library/LaunchDaemons/snort.plist -> /usr/local/snort-2.8.3/snort.plist 
(Note: It is common practice of mine to keep my homebrew launchd plists with the scripts or binaries themselves, and put sym links in /Library/LaunchDaemons/ or ~/Library/LaunchAgents/)
Thanx, anybody, in advance for any help that you can provide.

Answer 1

1. You should get rid of the "®" in your plist for reasons both legal and syntactic--the Snort logo is a registered trademark on the PTO's principal register, the word "snort" is not.
It would seem that the ServiceDescription functionality, recognized in Tiger, is no longer recognized as a valid launchd.plist keyword in Leopard. The console log indicates that this is now an unrecognized key word -- in each and every one of my launchd items. That keyword, along with its string, was removed. It didn't help, however.
2. You should not be symlinking anything.
Symlinking launchd plists has never, ever caused me problems before, and I have probably a half dozen symlinked plists. But, in the interest of trying to get this to work properly, I rm'ed the symlink, and mv'ed the actual plist to /Library/LaunchDaemons. Didn't cure the problem, though.
3. You should be using *launchctl load* for immediate feedback.
Thanks for that. I can never remember that command name!
4. You should read these cover-to-cover:
http://developer.apple.com/macosx/launchd.html
http://developer.apple.com/technotes/tn2005/tn2083.html
OK - done - nothing there jumped out at me as problems with what I was doing, but, handy references to have lying around. I'm already practicing the convention discussed therein that non-user-specific, homebrew, faceless jobs should go in the /Library/LaunchDaemons folder, as would make sense for a NIDS. So I'm not sure if you had something specific in mind when citing these articles or not....