Index: src/org/python/core/PyType.java
===================================================================
--- src/org/python/core/PyType.java	(revision 7067)
+++ src/org/python/core/PyType.java	(working copy)
@@ -22,6 +22,9 @@
 import org.python.modules._weakref.WeakrefModule;
 import org.python.util.Generic;
 
+import com.google.common.collect.MapMaker;
+import java.util.concurrent.ConcurrentMap;
+
 /**
  * The Python Type object implementation.
  */
@@ -96,8 +99,8 @@
     private static final MethodCache methodCache = new MethodCache();
 
     /** Mapping of Java classes to their PyTypes. */
-    private static Map<Class<?>, PyType> class_to_type;
-
+    private static ConcurrentMap<Class<?>, PyType> class_to_type;
+    
     /** Mapping of Java classes to their TypeBuilders. */
     private static Map<Class<?>, TypeBuilder> classToBuilder;
 
@@ -121,7 +124,15 @@
                                         PyObject[] args, String[] keywords) {
         // Special case: type(x) should return x.getType()
         if (args.length == 1 && keywords.length == 0) {
-            return args[0].getType();
+            PyObject obj = args[0];
+            PyType objType = obj.getType();
+
+            // special case for PyStringMap so that it types as a dict
+            PyType psmType = PyType.fromClass(PyStringMap.class);
+            if (objType == psmType) {
+                return PyDictionary.TYPE;
+            }
+            return objType;
         }
         // If that didn't trigger, we need 3 arguments. but ArgParser below may give a msg
         // saying type() needs exactly 3.
@@ -1251,11 +1262,14 @@
         return newtype;
     }
 
-    // XXX what's the proper scope of this synchronization? given module import lock, might be
-    // ok to omit this sync here...
+    // re the synchronization used here: this result is cached in each type obj,
+    // so we just need to prevent data races. all public methods that access class_to_type
+    // are themselves synchronized. However, if we use Google Collections/Guava,
+    // MapMaker only uses ConcurrentMap anyway
+
     public static synchronized PyType fromClass(Class<?> c) {
         if (class_to_type == null) {
-            class_to_type = Generic.synchronizedWeakHashMap();
+            class_to_type = new MapMaker().weakKeys().weakValues().makeMap();
             addFromClass(PyType.class, null);
         }
         PyType type = class_to_type.get(c);
Index: src/org/python/modules/zipimport/zipimporter.java
===================================================================
--- src/org/python/modules/zipimport/zipimporter.java	(revision 7067)
+++ src/org/python/modules/zipimport/zipimporter.java	(working copy)
@@ -117,7 +117,7 @@
                 zipimport._zip_directory_cache.__setitem__(archive, files);
             }
         } else {
-            throw zipimport.ZipImportError("not a Zip file");
+            throw zipimport.ZipImportError("not a Zip file: " + path);
         }
 
         if (prefix != "" && !prefix.endsWith(File.separator)) {
Index: src/org/python/util/Generic.java
===================================================================
--- src/org/python/util/Generic.java	(revision 7067)
+++ src/org/python/util/Generic.java	(working copy)
@@ -58,11 +58,6 @@
         return new HashMap<K, V>();
     }
 
-    public static <K, V> Map<K, V> synchronizedWeakHashMap() {
-        return Collections.synchronizedMap(new WeakHashMap<K, V>());
-    }
-
-
     /**
      * Makes a ConcurrentMap using generic types inferred from whatever this is being
      * assigned to.
Index: build.xml
===================================================================
--- build.xml	(revision 7067)
+++ build.xml	(working copy)
@@ -188,6 +188,7 @@
             <pathelement path="${extlibs.dir}/asm-3.1.jar" />
             <pathelement path="${extlibs.dir}/asm-commons-3.1.jar" />
             <pathelement path="${extlibs.dir}/constantine.jar" />
+            <pathelement path="${extlibs.dir}/guava-r05.jar" />
             <pathelement path="${extlibs.dir}/jaffl.jar"/>
             <pathelement path="${extlibs.dir}/jffi-Darwin.jar"/>
             <pathelement path="${extlibs.dir}/jffi-i386-FreeBSD.jar"/>
@@ -584,6 +585,8 @@
             <zipfileset src="extlibs/asm-commons-3.1.jar"/>
             <zipfileset src="extlibs/asm-util-3.1.jar"/>
             <rule pattern="org.objectweb.asm.**" result="org.python.objectweb.asm.@1"/>
+            <zipfileset src="extlibs/guava-r05.jar"/>
+            <rule pattern="com.google.**" result="org.python.google.@1"/>
             <zipfileset src="extlibs/jaffl.jar"/>
             <zipfileset src="extlibs/jffi-Darwin.jar"/>
             <zipfileset src="extlibs/jffi-i386-FreeBSD.jar"/>