diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
index 95223a44b..28a05ff21 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
@@ -821,12 +821,15 @@ public class SimpleFunctionRegistry implements FunctionRegistry, FunctionInspect
 
 						boolean convertWithHint = false;
 						Type hint = FunctionTypeUtils.getGenericType(type);
-						if (FunctionTypeUtils.isTypeCollection(type)) {
-							convertWithHint = true;
-						}
-						else if (!FunctionTypeUtils.isPublisher(type) && !rawType.equals(type)) {
-							convertWithHint = true;
-						}
+
+						convertWithHint = this.useConversionHint(type, rawType);
+
+//						if (FunctionTypeUtils.isTypeCollection(type)) {
+//							convertWithHint = true;
+//						}
+//						else if (!FunctionTypeUtils.isPublisher(type) && !rawType.equals(type) && !FunctionTypeUtils.isMessage(type)) {
+//							convertWithHint = true;
+//						}
 
 						convertedValue = convertWithHint
 							? this.fromMessage((Message<?>) value, (Class<?>) rawType, hint)
@@ -864,6 +867,16 @@ public class SimpleFunctionRegistry implements FunctionRegistry, FunctionInspect
 			return convertedValue;
 		}
 
+		private boolean useConversionHint(Type type, Type rawType) {
+			if (FunctionTypeUtils.isTypeCollection(type)) {
+				return true;
+			}
+			else if (!FunctionTypeUtils.isPublisher(type) && !rawType.equals(type) && !FunctionTypeUtils.isMessage(type)) {
+				return true;
+			}
+			return false;
+		}
+
 		private Object convertNonMessageInputIfNecessary(Type inputType, Object input) {
 			Object convertedInput = input;
 			Class<?> rawInputType = FunctionTypeUtils.isReactive(inputType) || FunctionTypeUtils.isMessage(inputType)
diff --git a/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/catalog/BeanFactoryAwareFunctionRegistryTests.java b/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/catalog/BeanFactoryAwareFunctionRegistryTests.java
index fce467ca8..d7a55f242 100644
--- a/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/catalog/BeanFactoryAwareFunctionRegistryTests.java
+++ b/spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/catalog/BeanFactoryAwareFunctionRegistryTests.java
@@ -546,6 +546,23 @@ public class BeanFactoryAwareFunctionRegistryTests {
 		assertThat(((Person) config.consumerInputRef.get()).getName()).isEqualTo("Ricky");
 	}
 
+	@Test
+	public void testGH_608_B() {
+		ApplicationContext context = new SpringApplicationBuilder(MessageFunctionConfiguration.class)
+				.run("--logging.level.org.springframework.cloud.function=DEBUG",
+						"--spring.main.lazy-initialization=true");
+		FunctionCatalog catalog = context.getBean(FunctionCatalog.class);
+
+		String productJson = "{\"name\":\"bike\"}";
+		FunctionInvocationWrapper function = catalog.lookup("echo", "application/json");
+		Message<byte[]> result = (Message<byte[]>) function.apply(productJson);
+		assertThat(productJson).isEqualTo(new String(result.getPayload()));
+
+		function = catalog.lookup("echoFlux", "application/json");
+		result = ((Flux<Message<byte[]>>) function.apply("{\"name\":\"bike\"}")).blockFirst();
+		assertThat(productJson).isEqualTo(new String(result.getPayload()));
+	}
+
 	@Test
 	public void testGH_609() {
 		FunctionCatalog catalog = this.configureCatalog(SampleFunctionConfiguration.class);
@@ -803,6 +820,21 @@ public class BeanFactoryAwareFunctionRegistryTests {
 		}
 	}
 
+	@EnableAutoConfiguration
+	@Configuration
+	protected static class MessageFunctionConfiguration {
+
+		@Bean
+		public Function<Message<Product>, Message<Product>> echo() {
+			return x -> x;
+		}
+
+		@Bean
+		public Function<Flux<Message<Product>>, Flux<Message<Product>>> echoFlux() {
+			return x -> x;
+		}
+	}
+
 	@EnableAutoConfiguration
 	@Configuration
 	protected static class SampleFunctionConfiguration {