Add a note regarding dependency overriding

Fixes gh-958

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

@@ -1446,9 +1446,10 @@ would only ever be a development time trick probably).
 
 [[howto-customize-dependency-versions-with-maven]]
 === Customize dependency versions with Maven
-If you use a Maven build that inherits from `spring-boot-starter-parent` but you want
-to override a specific third-party dependency you can add appropriate `<properties>`
-elements. Browse the {github-code}/spring-boot-dependencies/pom.xml[`spring-dependencies`]
+If you use a Maven build that inherits directly or indirectly from `spring-boot-dependencies`
+(for instance `spring-boot-starter-parent`) but you want to override a specific
+third-party dependency you can add appropriate `<properties>` elements. Browse
+the {github-code}/spring-boot-dependencies/pom.xml[`spring-boot-dependencies`]
 POM for a complete list of properties. For example, to pick a different `slf4j` version
 you would add the following:
 
@@ -1459,6 +1460,11 @@ you would add the following:
 	</properties>
 ----
 
+NOTE: this only works if your Maven project inherits (directly or indirectly) from
+`spring-boot-dependencies`. If you have added `spring-boot-dependencies` in your
+own `dependencyManagement` section with `<scope>import</scope>` you have to redefine
+the artifact yourself instead of overriding the property	.
+
 WARNING: Each Spring Boot release is designed and tested against a specific set of
 third-party dependencies. Overriding versions may cause compatibility issues.