This is Ken Cheung, a Computer Science M.Phil. student. I observed some
code clones in Tomcat and found inconsistent code:

/tomcat/trunk/java/org/apache/catalina/realm/JDBCRealm.java

676	        if (driver == null) {
677	            try {
678	                Class<?> clazz = Class.forName(driverName);
679	                driver = (Driver) clazz.newInstance();
680	            } catch (Throwable e) {
681	                ExceptionUtils.handleThrowable(e);
682	                throw new SQLException(e.getMessage(), e);
683	            }
684	        }
685	
686	        // Open a new connection
687	        Properties props = new Properties();
688	        if (connectionName != null)
689	            props.put("user", connectionName);
690	        if (connectionPassword != null)
691	            props.put("password", connectionPassword);
692	        dbConnection = driver.connect(connectionURL, props);

/tomcat/trunk/java/org/apache/catalina/valves/JDBCAccessLogValve.java

566	        if (driver == null) {
567	            try {
568	                Class<?> clazz = Class.forName(driverName);
569	                driver = (Driver) clazz.newInstance();
570	            } catch (Throwable e) {
571	                ExceptionUtils.handleThrowable(e);
572	                throw new SQLException(e.getMessage(), e);
573	            }
574	        }
575	
576	        // Open a new connection
577	        Properties props = new Properties();
578	        props.put("autoReconnect", "true");
579	        if (connectionName != null) {
580	            props.put("user", connectionName);
581	        }
582	        if (connectionPassword != null) {
583	            props.put("password", connectionPassword);
584	        }
585	        conn = driver.connect(connectionURL, props);

Quick description of the inconsistency
Two code snippets are very similar code, but as you see, in JDBCRealm.java does not use "props.put("autoReconnect", "true")" while JDBCAccessLogValve.java has.

We thought it could be a potential bug or inconsistency. Hope this helps.