sudo syslog weirdness

On one of my machines I am having some weirdness with syslog. It runs differently, with a lot less information, if I escalate to root privilege. For example,

$ syslog

shows results from Jul 25 18:49:21 to Feb 5 18:06:16 (piping the results through "more" and "tail")

$ sudo syslog

only shows results from Dec 31 10:53:58 to Jan 31 19:17:12. For example, *nothing* for February.

I only get this on my Mac Pro running Mt. Lion. My other machines show the same result whether I am running them with sudo or not.

Unfortunately, for some esoteric reasons I need to run syslog as root to harvest the lastest logs.

Any help as to how to resolve this would be appreciated!