diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/maven/archiva/repository/content/AbstractDefaultRepositoryContent.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/maven/archiva/repository/content/AbstractDefaultRepositoryContent.java
index a8556c9cc..062dd7d13 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/maven/archiva/repository/content/AbstractDefaultRepositoryContent.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/maven/archiva/repository/content/AbstractDefaultRepositoryContent.java
@@ -63,7 +63,7 @@ public abstract class AbstractDefaultRepositoryContent
      * plexus.requirement role="org.apache.archiva.metadata.repository.storage.maven2.ArtifactMappingProvider"
      */
     @Inject
-    protected List<ArtifactMappingProvider> artifactMappingProviders;
+    protected List<? extends ArtifactMappingProvider> artifactMappingProviders;
 
     //@Inject
     //protected ApplicationContext applicationContext;