Here's the solution.
I also had to change the permissions, owner, and group for log4j.properties after copying it into /usr/share/tomcat/lib.
http://wiki.apache.org/solr/SolrLogging
Using the example logging setup in containers other than Jetty
To get the same logging setup in another container (Tomcat for example) as with the example Jetty server, you need to do the following
Copy the jars from solr/example/lib/ext into your container's main lib directory. These jars will set up SLF4J and log4j.
Exactly where this lib directory is highly variable. For a Debian or Ubuntu server using the Tomcat package available from the OS vendor, this is likely to be /usr/share/tomcat6/lib or /usr/share/tomcat7/lib.
Copy the logging config from solr/example/resources/log4j.properties into a location on the classpath. Usually you can use the same location as the jar files above. Edit the configuration file for your preferred log destination.
Optionally, if you did not place log4j.properties on the classpath, set
java option -Dlog4j.configuration=file:///path/to/log4j.properties
If the system can not find the jars for logging, you may get an error which prevents Solr from deploying. For instance in Tomcat 6, it might look like this:
INFO: Deploying web application archive solr.war
May 29, 2013 3:59:40 PM org.apache.catalina.core.StandardContext start
SEVERE: Error filterStart
May 29, 2013 3:59:40 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [/solr] startup failed due to previous errors
If the system cannot find your logging configuration, you may get errors like this:
log4j:WARN No appenders could be found for logger (org.apache.solr.servlet.SolrDispatchFilter).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See
http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
It might help to start the server with -Dlog4j.debug=true to see more details.