about Tomcat show "INFO: Additional JARs have been added"

Jun 6, 2009 1:54:19 PM org.apache.catalina.loader.WebappClassLoader modified
INFO: Additional JARs have been added
Jun 6, 2009 1:54:19 PM org.apache.catalina.core.StandardContext reload
INFO: Reloading this Context has started
Jun 6, 2009 1:54:29 PM org.apache.catalina.loader.WebappClassLoader modified
INFO: Additional JARs have been added
Jun 6, 2009 1:54:29 PM org.apache.catalina.core.StandardContext reload
INFO: Reloading this Context has started
Jun 6, 2009 1:54:39 PM org.apache.catalina.loader.WebappClassLoader modified
INFO: Additional JARs have been added
Jun 6, 2009 1:54:39 PM org.apache.catalina.core.StandardContext reload
INFO: Reloading this Context has started

I had made a project, but when I started up tomcat, these message were shown in console.
they are borning.
Then I found the reason.For connect to Oracle DB, I had added a ojdbc.jar to $PROJECT/WEB-INF/lib/ folder.The attributte of it is "-rw-r-----". because I am using a normal user to startup tomcat, I have no access privilege to it . I changed the attribute to 644, it works correctly.

I am using java1.6, tomcat6.0, eclipse3.4(all in one).