diff --git a/spring-beans/src/main/java/org/springframework/beans/TypeConverterDelegate.java b/spring-beans/src/main/java/org/springframework/beans/TypeConverterDelegate.java
index 9776b460b7..64f437320f 100644
--- a/spring-beans/src/main/java/org/springframework/beans/TypeConverterDelegate.java
+++ b/spring-beans/src/main/java/org/springframework/beans/TypeConverterDelegate.java
@@ -44,6 +44,7 @@ import org.springframework.util.StringUtils;
  *
  * @author Juergen Hoeller
  * @author Rob Harrop
+ * @author Dave Syer
  * @since 2.0
  * @see BeanWrapperImpl
  * @see SimpleTypeConverter
@@ -244,7 +245,7 @@ class TypeConverterDelegate {
 		}
 
 		if (firstAttemptEx != null) {
-			if (editor == null && convertedValue == newValue) {
+			if (editor == null && convertedValue == newValue && requiredType!=null && !ClassUtils.isAssignableValue(requiredType, convertedValue)) {
 				throw firstAttemptEx;
 			}
 			logger.debug("Original ConversionService attempt failed - ignored since " +
diff --git a/spring-beans/src/test/java/org/springframework/beans/BeanWrapperTests.java b/spring-beans/src/test/java/org/springframework/beans/BeanWrapperTests.java
index 49c301284a..f6e68234bb 100644
--- a/spring-beans/src/test/java/org/springframework/beans/BeanWrapperTests.java
+++ b/spring-beans/src/test/java/org/springframework/beans/BeanWrapperTests.java
@@ -43,14 +43,16 @@ import java.util.TreeMap;
 import java.util.TreeSet;
 
 import org.apache.commons.logging.LogFactory;
-import org.junit.Ignore;
 import org.junit.Test;
 import org.springframework.beans.factory.annotation.Autowire;
 import org.springframework.beans.propertyeditors.CustomNumberEditor;
 import org.springframework.beans.propertyeditors.StringArrayPropertyEditor;
 import org.springframework.beans.propertyeditors.StringTrimmerEditor;
 import org.springframework.beans.support.DerivedFromProtectedBaseBean;
+import org.springframework.core.convert.ConversionFailedException;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.core.convert.support.DefaultConversionService;
+import org.springframework.core.convert.support.GenericConversionService;
 import org.springframework.util.StopWatch;
 import org.springframework.util.StringUtils;
 
@@ -66,9 +68,34 @@ import test.beans.TestBean;
  * @author Alef Arendsen
  * @author Arjen Poutsma
  * @author Chris Beams
+ * @author Dave Syer
  */
 public final class BeanWrapperTests {
 
+	@Test
+	public void testNullNestedTypeDescriptorWithNoConversionService() {
+		Foo foo = new Foo();
+		BeanWrapperImpl wrapper = new BeanWrapperImpl(foo);
+		wrapper.setAutoGrowNestedPaths(true);
+		wrapper.setPropertyValue("listOfMaps[0]['luckyNumber']", "9");
+		assertEquals("9", foo.listOfMaps.get(0).get("luckyNumber"));
+	}
+	
+	@Test
+	public void testNullNestedTypeDescriptorWithBadConversionService() {
+		Foo foo = new Foo();
+		BeanWrapperImpl wrapper = new BeanWrapperImpl(foo);
+		wrapper.setConversionService(new GenericConversionService() {
+			@Override
+			public Object convert(Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
+				throw new ConversionFailedException(sourceType, targetType, source, null);
+			}
+		});
+		wrapper.setAutoGrowNestedPaths(true);
+		wrapper.setPropertyValue("listOfMaps[0]['luckyNumber']", "9");
+		assertEquals("9", foo.listOfMaps.get(0).get("luckyNumber"));
+	}
+	
 	@Test
 	public void testNullNestedTypeDescriptor() {
 		Foo foo = new Foo();