diff --git a/org.springframework.core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java b/org.springframework.core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java
index e4519ee27980628813be238342a3e4048d07717b..894dfcd0234fd06ff05300275e18e91e56241b8d 100644
--- a/org.springframework.core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java
+++ b/org.springframework.core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java
@@ -172,7 +172,13 @@ public class GenericConversionService implements ConversionService, ConverterReg
 		}
 		GenericConverter converter = getConverter(sourceType, targetType);
 		if (converter == null) {
-			throw new ConverterNotFoundException(sourceType, targetType);
+			if (targetType.getType().isInstance(source)) {
+				logger.debug("No converter found - returning assignable source object as-is");
+				return source;
+			}
+			else {
+				throw new ConverterNotFoundException(sourceType, targetType);
+			}
 		}
 		Object result = ConversionUtils.invokeConverter(converter, source, sourceType, targetType);
 		if (logger.isDebugEnabled()) {
diff --git a/org.springframework.expression/src/test/java/org/springframework/expression/spel/standard/PropertiesConversionSpelTests.java b/org.springframework.expression/src/test/java/org/springframework/expression/spel/standard/PropertiesConversionSpelTests.java
index 6c1c47f508754277680d5d0639d54f0f5a1facfa..ebac11450efda4beff0c10a141c955bab6752893 100644
--- a/org.springframework.expression/src/test/java/org/springframework/expression/spel/standard/PropertiesConversionSpelTests.java
+++ b/org.springframework.expression/src/test/java/org/springframework/expression/spel/standard/PropertiesConversionSpelTests.java
@@ -21,6 +21,7 @@ import static org.junit.Assert.assertEquals;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
+import java.util.UUID;
 
 import org.junit.Test;
 
@@ -61,12 +62,26 @@ public class PropertiesConversionSpelTests {
 		assertEquals("123", result);
 	}
 
-	@Test // questionable, but this passes with 3.0.2.RELEASE
+	@Test
 	public void mapWithNonStringValue() {
 		Map<String, Object> map = new HashMap<String, Object>();
 		map.put("x", "1");
 		map.put("y", 2);
 		map.put("z", "3");
+		map.put("a", new UUID(1, 1));
+		Expression expression = parser.parseExpression("foo(#props)");
+		StandardEvaluationContext context = new StandardEvaluationContext();
+		context.setVariable("props", map);
+		String result = expression.getValue(context, new TestBean(), String.class);
+		assertEquals("1null3", result);
+	}
+
+	@Test
+	public void customMapWithNonStringValue() {
+		CustomMap map = new CustomMap();
+		map.put("x", "1");
+		map.put("y", 2);
+		map.put("z", "3");
 		Expression expression = parser.parseExpression("foo(#props)");
 		StandardEvaluationContext context = new StandardEvaluationContext();
 		context.setVariable("props", map);
@@ -83,4 +98,9 @@ public class PropertiesConversionSpelTests {
 		}
 	}
 
+
+	@SuppressWarnings("serial")
+	private static class CustomMap extends HashMap<String, Object> {
+	}
+
 }