diff --git a/extensions/arc/deployment/src/main/java/io/quarkus/arc/deployment/ArcProcessor.java b/extensions/arc/deployment/src/main/java/io/quarkus/arc/deployment/ArcProcessor.java
index 6b2df3ce56c7f..f8f0e332c0455 100644
--- a/extensions/arc/deployment/src/main/java/io/quarkus/arc/deployment/ArcProcessor.java
+++ b/extensions/arc/deployment/src/main/java/io/quarkus/arc/deployment/ArcProcessor.java
@@ -441,9 +441,22 @@ public ObserverRegistrationPhaseBuildItem registerSyntheticObservers(BeanRegistr
             // Note that at this point we can be sure that the required type is List<>
             Type typeParam = injectionPoint.getType().asParameterizedType().arguments().get(0);
             if (typeParam.kind() == Type.Kind.WILDCARD_TYPE) {
-                validationErrors.produce(new ValidationErrorBuildItem(
-                        new DefinitionException(
-                                "Wildcard is not a legal type argument for " + injectionPoint.getTargetInfo())));
+                ClassInfo declaringClass;
+                if (injectionPoint.isField()) {
+                    declaringClass = injectionPoint.getTarget().asField().declaringClass();
+                } else {
+                    declaringClass = injectionPoint.getTarget().asMethod().declaringClass();
+                }
+                if (declaringClass.classAnnotation(DotNames.KOTLIN_METADATA_ANNOTATION) != null) {
+                    validationErrors.produce(new ValidationErrorBuildItem(
+                            new DefinitionException(
+                                    "kotlin.collections.List cannot be used together with the @All qualifier, please use MutableList or java.util.List instead: "
+                                            + injectionPoint.getTargetInfo())));
+                } else {
+                    validationErrors.produce(new ValidationErrorBuildItem(
+                            new DefinitionException(
+                                    "Wildcard is not a legal type argument for " + injectionPoint.getTargetInfo())));
+                }
             } else if (typeParam.kind() == Type.Kind.TYPE_VARIABLE) {
                 validationErrors.produce(new ValidationErrorBuildItem(new DefinitionException(
                         "Type variable is not a legal type argument for " + injectionPoint.getTargetInfo())));
diff --git a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/DotNames.java b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/DotNames.java
index 2aa648d90dd37..e7272bf380d54 100644
--- a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/DotNames.java
+++ b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/DotNames.java
@@ -128,6 +128,8 @@ public final class DotNames {
     public static final DotName IDENTIFIED = create(Identified.class);
     public static final DotName INSTANCE_HANDLE = create(InstanceHandle.class);
     public static final DotName NO_CLASS_INTERCEPTORS = create(NoClassInterceptors.class);
+    public static final DotName DEPRECATED = create(Deprecated.class);
+    public static final DotName KOTLIN_METADATA_ANNOTATION = create("kotlin.Metadata");
 
     public static final DotName BOOLEAN = create(Boolean.class);
     public static final DotName BYTE = create(Byte.class);
@@ -139,8 +141,6 @@ public final class DotNames {
     public static final DotName SHORT = create(Short.class);
     public static final DotName STRING = create(String.class);
 
-    public static final DotName DEPRECATED = create(Deprecated.class);
-
     private DotNames() {
     }
 
diff --git a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/SubclassGenerator.java b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/SubclassGenerator.java
index 9fe7af99568af..71cf4847d8a1c 100644
--- a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/SubclassGenerator.java
+++ b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/SubclassGenerator.java
@@ -65,7 +65,6 @@ public class SubclassGenerator extends AbstractGenerator {
     private static final DotName JAVA_LANG_THROWABLE = DotNames.create(Throwable.class.getName());
     private static final DotName JAVA_LANG_EXCEPTION = DotNames.create(Exception.class.getName());
     private static final DotName JAVA_LANG_RUNTIME_EXCEPTION = DotNames.create(RuntimeException.class.getName());
-    private static final DotName KOTLIN_METADATA_ANNOTATION = DotNames.create("kotlin.Metadata");
 
     static final String SUBCLASS_SUFFIX = "_Subclass";
     static final String DESTROY_METHOD_NAME = "arc$destroy";
@@ -750,7 +749,7 @@ private void createInterceptedMethod(ClassOutput classOutput, BeanInfo bean, Met
         // catch exceptions declared on the original method
         boolean addCatchRuntimeException = true;
         boolean addCatchException = true;
-        boolean isKotlin = method.declaringClass().classAnnotation(KOTLIN_METADATA_ANNOTATION) != null;
+        boolean isKotlin = method.declaringClass().classAnnotation(DotNames.KOTLIN_METADATA_ANNOTATION) != null;
         Set<DotName> declaredExceptions = new LinkedHashSet<>(method.exceptions().size());
         for (Type declaredException : method.exceptions()) {
             declaredExceptions.add(declaredException.name());