Merge branch '1.5.x'

spring-boot-project/spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -1513,6 +1513,11 @@ output using Log4j 2). See the
 {github-code}/spring-boot-samples/spring-boot-sample-actuator-log4j2[Actuator Log4j 2]
 samples for more detail and to see it in action.
 
+NOTE: To ensure that debug logging performed using `java.util.logging` is routed into
+Log4j 2, configure its https://logging.apache.org/log4j/2.0/log4j-jul/index.html[JDK
+logging adapter] by setting the `java.util.logging.manager` system property to
+`org.apache.logging.log4j.jul.LogManager`.
+
 
 
 [[howto-configure-log4j-for-logging-yaml-or-json-config]]