Index: src/main/org/codehaus/groovy/runtime/metaclass/ClosureMetaMethod.java
===================================================================
--- src/main/org/codehaus/groovy/runtime/metaclass/ClosureMetaMethod.java	(revision 13802)
+++ src/main/org/codehaus/groovy/runtime/metaclass/ClosureMetaMethod.java	(working copy)
@@ -99,7 +99,8 @@
             Class ownerClass = (Class) (owner instanceof Class ? owner : owner.getClass());
             for (CachedMethod method : ReflectionCache.getCachedClass(ownerClass).getMethods() ) {
                 if (method.getName().equals(methodClosure.getMethod())) {
-                    res.add(new MethodClosureMetaMethod(name, declaringClass, closure, method));
+                	MetaMethod metaMethod = new MethodClosureMetaMethod(name, declaringClass, closure, method); 
+                    res.add(adjustParamTypesForStdMethods(metaMethod, name));
                 }
             }
         }
@@ -107,40 +108,53 @@
             if (closure instanceof GeneratedClosure) {
                 for (CachedMethod method : ReflectionCache.getCachedClass(closure.getClass()).getMethods() ) {
                     if (method.getName().equals("doCall")) {
-                        res.add(new ClosureMetaMethod(name, declaringClass, closure, method));
+                    	MetaMethod metaMethod = new ClosureMetaMethod(name, declaringClass, closure, method);
+                    	res.add(adjustParamTypesForStdMethods(metaMethod, name));
                     }
                 }
             }
             else {
-                res.add(new MetaMethod(closure.getParameterTypes()){
-                    public int getModifiers() {
-                        return Modifier.PUBLIC;
-                    }
-
-                    public String getName() {
-                        return name;
-                    }
-
-                    public Class getReturnType() {
-                        return Object.class;
-                    }
-
-                    public CachedClass getDeclaringClass() {
-                        return ReflectionCache.getCachedClass(declaringClass);
-                    }
-
-                    public Object invoke(Object object, Object[] arguments) {
-                        Closure cloned = (Closure) closure.clone();
-                        cloned.setDelegate(object);
-                        arguments = coerceArgumentsToClasses(arguments);
-                        return InvokerHelper.invokeMethod(closure, "call", arguments);
-                    }
-                });
+            	MetaMethod metaMethod =
+            		new MetaMethod(closure.getParameterTypes()){
+	                    public int getModifiers() {
+	                        return Modifier.PUBLIC;
+	                    }
+	
+	                    public String getName() {
+	                        return name;
+	                    }
+	
+	                    public Class getReturnType() {
+	                        return Object.class;
+	                    }
+	
+	                    public CachedClass getDeclaringClass() {
+	                        return ReflectionCache.getCachedClass(declaringClass);
+	                    }
+	
+	                    public Object invoke(Object object, Object[] arguments) {
+	                        Closure cloned = (Closure) closure.clone();
+	                        cloned.setDelegate(object);
+	                        arguments = coerceArgumentsToClasses(arguments);
+	                        return InvokerHelper.invokeMethod(closure, "call", arguments);
+	                    }
+	                };
+	                res.add(adjustParamTypesForStdMethods(metaMethod, name));
             }
         }
         return res;
     }
 
+    private static MetaMethod adjustParamTypesForStdMethods(MetaMethod metaMethod, String methodName) {
+		Class[] nativeParamTypes = metaMethod.getNativeParameterTypes();
+		nativeParamTypes = (nativeParamTypes != null) ? nativeParamTypes : new Class[0];
+		if("methodMissing".equals(methodName) && 
+				nativeParamTypes.length == 2 && nativeParamTypes[0] != String.class) {
+			nativeParamTypes[0] = String.class;
+		}
+    	return metaMethod;
+    }
+
     public CachedMethod getDoCall() {
         return doCall;
     }