diff --git a/pmd-kotlin/pom.xml b/pmd-kotlin/pom.xml
index d00109b502..f1d7cb3ce1 100644
--- a/pmd-kotlin/pom.xml
+++ b/pmd-kotlin/pom.xml
@@ -20,6 +20,9 @@
             <plugin>
                 <groupId>org.antlr</groupId>
                 <artifactId>antlr4-maven-plugin</artifactId>
+                <configuration combine.self="override">
+                    <libDirectory>src/main/antlr4/net/sourceforge/pmd/lang/kotlin/ast</libDirectory>
+                </configuration>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
diff --git a/pom.xml b/pom.xml
index c2739dcf74..470e267a50 100644
--- a/pom.xml
+++ b/pom.xml
@@ -136,7 +136,6 @@
                         <inputEncoding>${project.build.sourceEncoding}</inputEncoding>
                         <visitor>true</visitor>
                         <listener>true</listener>
-                        <libDirectory>src/main/antlr4/net/sourceforge/pmd/lang/kotlin/ast</libDirectory>
                     </configuration>
                     <executions>
                         <execution>