Hi Priya,
I'm not at all familiar with this product but I can suggest that:
1.) Unzip the OpenSSO war and see if they have a log4j.properties or log4j.xml, that should show you where their logs are going to.
2.) Since it is open source
you should be able to download the source code, add your own logging and build your own WAR.
3.) I suspect you'd need to be an administrator or some one with elevated privileges yes.