diff --git a/core/deployment/src/main/java/io/quarkus/deployment/builditem/GeneratedClassBuildItem.java b/core/deployment/src/main/java/io/quarkus/deployment/builditem/GeneratedClassBuildItem.java
index 00fb49e11a23b..eb3a1df5f3968 100644
--- a/core/deployment/src/main/java/io/quarkus/deployment/builditem/GeneratedClassBuildItem.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/builditem/GeneratedClassBuildItem.java
@@ -18,7 +18,7 @@ public GeneratedClassBuildItem(boolean applicationClass, String name, byte[] cla
             throw new IllegalArgumentException("Name cannot start with '/':" + name);
         }
         this.applicationClass = applicationClass;
-        this.name = name;
+        this.name = name.replace('/', '.');
         this.classData = classData;
         this.source = source;
     }
@@ -39,4 +39,7 @@ public String getSource() {
         return source;
     }
 
+    public String toString() {
+        return "GeneratedClassBuildItem[" + name + "]";
+    }
 }
diff --git a/extensions/smallrye-reactive-messaging-kafka/deployment/src/test/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeConfigTest.java b/extensions/smallrye-reactive-messaging-kafka/deployment/src/test/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeConfigTest.java
index cc971ba643bcb..c8620fbaae5f4 100644
--- a/extensions/smallrye-reactive-messaging-kafka/deployment/src/test/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeConfigTest.java
+++ b/extensions/smallrye-reactive-messaging-kafka/deployment/src/test/java/io/quarkus/smallrye/reactivemessaging/kafka/deployment/DefaultSerdeConfigTest.java
@@ -132,10 +132,12 @@ boolean isKafkaConnector(List<ConnectorManagedChannelBuildItem> list, boolean in
 
             assertThat(generated)
                     .extracting(GeneratedClassBuildItem::getName)
+                    .extracting(n -> n.replace('/', '.'))
                     .allSatisfy(s -> assertThat(generatedNames).satisfiesOnlyOnce(c -> c.apply(s)));
 
             assertThat(reflective)
                     .flatExtracting(ReflectiveClassBuildItem::getClassNames)
+                    .extracting(n -> n.replace('/', '.'))
                     .allSatisfy(s -> assertThat(reflectiveNames).satisfiesOnlyOnce(c -> c.apply(s)));
         } finally {
             // must not leak the lazily-initialized Config instance associated to the system classloader