Index: src/org/jruby/javasupport/JavaClass.java
===================================================================
--- src/org/jruby/javasupport/JavaClass.java	(revision 3480)
+++ src/org/jruby/javasupport/JavaClass.java	(working copy)
@@ -45,9 +45,11 @@
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -182,11 +184,31 @@
         return JavaClass.get(recv.getRuntime(), klass);
     }
     
+
+    private Set getPublicFieldNames(boolean isStatic) {
+        // we're not checking for final here; since the purpose is to prevent
+        // shortcut property names from being created that conflict with
+        // field names, it won't make sense to allow the property setter (name=)
+        // to be created but not the getter.
+        int mask = Modifier.PUBLIC | Modifier.STATIC;
+        int want = isStatic ? Modifier.PUBLIC | Modifier.STATIC : Modifier.PUBLIC;
+        Set names = new HashSet();
+        names.add("class");
+        Field[] fields = ((Class)getValue()).getFields();
+        for (int i = fields.length; --i >= 0; ) {
+            if ((fields[i].getModifiers() & mask) == want) {
+                names.add(fields[i].getName());
+            }
+        }
+        return names;
+    }
+    
+    
     /**
      *  Get all methods grouped by name (e.g. 'new => {new(), new(int), new(int, int)}, ...')
      *  @param isStatic determines whether you want static or instance methods from the class
      */
-    private Map getMethodsClumped(boolean isStatic) {
+    private Map getMethodsClumped(boolean isStatic, Set assignedNames) {
         Map map = new HashMap();
         if(((Class)getValue()).isInterface()) {
             return map;
@@ -205,6 +227,7 @@
             if (methodsWithName == null) {
                 methodsWithName = RubyArray.newArrayLight(getRuntime());
                 map.put(key, methodsWithName);
+                assignedNames.add(key);
             }
             
             methodsWithName.append(JavaMethod.create(getRuntime(), methods[i]));
@@ -213,7 +236,7 @@
         return map;
     }
     
-    private Map getPropertysClumped() {
+    private Map getPropertysClumped(Set assignedNames) {
         Map map = new HashMap();
         BeanInfo info;
         
@@ -242,7 +265,9 @@
                     readMethod.getReturnType() == boolean.class) {
                     aliases.add(descriptors[i].getName() + "?");
                 }
-                aliases.add(descriptors[i].getName());
+                if (!assignedNames.contains(descriptors[i].getName())) {
+                    aliases.add(descriptors[i].getName());
+                }
             }
             
             Method writeMethod = descriptors[i].getWriteMethod();
@@ -256,7 +281,9 @@
                     map.put(key, aliases);
                 }
                 
-                aliases.add(descriptors[i].getName()  + "=");
+                if (!assignedNames.contains(descriptors[i].getName())) {
+                    aliases.add(descriptors[i].getName()  + "=");
+                }
             }
         }
         
@@ -369,8 +396,9 @@
     public IRubyObject define_instance_methods_for_proxy(IRubyObject arg) {
         assert arg instanceof RubyClass;
 
-        Map aliasesClump = getPropertysClumped();
-        Map methodsClump = getMethodsClumped(false);
+        Set assignedNames = getPublicFieldNames(false);
+        Map methodsClump = getMethodsClumped(false,assignedNames);
+        Map aliasesClump = getPropertysClumped(assignedNames);
         RubyClass proxy = (RubyClass) arg;
 
         proxy.defineFastMethod("__jsend!", __jsend_method);
@@ -525,6 +553,8 @@
     }
     
     public RubyArray declared_classes() {
+       // TODO: should be able to partially work around this by calling
+       // javaClass().getClasses, which will return any public inner classes.
        if (Ruby.isSecurityRestricted()) // Can't even get inner classes?
            return getRuntime().newArray(0);
         Class[] classes = javaClass().getDeclaredClasses();