log4j

Anyone have experience with Apache's log4j?

I just downloaded it today and started playing around. I can get the BasicConfigurator working easy enough, now I'm trying to use the PropertyConfigurator to customiz the logs.
The documentation says to put the log4j.properties file in the WEB-INF/classes dir. Which I did, and in the code I'm calling it like this...

PropertyConfigurator.configure("/classes/log4j.properties");

But when I run, it gives an log4j error, ERROR Could not read configuration file [/classes/log4j.properties]
then throws a file not found exception, then another log4j error, ERROR Ignoring configuration file [/classes/log4j.properties].

But here's the odd part, any changes I make to log4j.properties still come up.
Any idea why I'm getting the errors?

thanks