diff --git a/test-runner/android/test/InstrumentationCoreTestRunner.java b/test-runner/android/test/InstrumentationCoreTestRunner.java
index 6b1a4e4..3f77a60 100644
--- a/test-runner/android/test/InstrumentationCoreTestRunner.java
+++ b/test-runner/android/test/InstrumentationCoreTestRunner.java
@@ -17,27 +17,158 @@
 package android.test;
 
 import java.io.File;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.util.List;
 
+import com.android.internal.util.Predicate;
+import com.android.internal.util.Predicates;
+
+import dalvik.annotation.BrokenTest;
+import dalvik.annotation.SideEffect;
+
+import junit.framework.AssertionFailedError;
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestListener;
 import android.os.Bundle;
+import android.test.suitebuilder.TestMethod;
+import android.test.suitebuilder.annotation.HasAnnotation;
+import android.util.Log;
 
 /**
  * This test runner extends the default InstrumentationTestRunner. It overrides
  * the {@code onCreate(Bundle)} method and sets the system properties necessary
  * for many core tests to run. This is needed because there are some core tests
- * that need writing access to the filesystem.
+ * that need writing access to the file system. We also need to set the harness
+ * Thread's context ClassLoader. Otherwise some classes and resources will not
+ * be found. Finally, we add a means to free memory allocated by a TestCase
+ * after its execution.
  *
  * @hide
  */
 public class InstrumentationCoreTestRunner extends InstrumentationTestRunner {
 
+    private static final String TAG = "InstrumentationCoreTestRunner";
+    private boolean singleTest = false;
+    
     @Override
     public void onCreate(Bundle arguments) {
-        super.onCreate(arguments);
-        
+        // We might want to move this to /sdcard, if is is mounted/writable.
         File cacheDir = getTargetContext().getCacheDir();
 
         System.setProperty("user.language", "en");
         System.setProperty("user.region", "US");
+        
+        System.setProperty("java.home", cacheDir.getAbsolutePath());
+        System.setProperty("user.home", cacheDir.getAbsolutePath());
         System.setProperty("java.io.tmpdir", cacheDir.getAbsolutePath());
+        System.setProperty("javax.net.ssl.trustStore",
+                "/etc/security/cacerts.bks");
+        
+        if (arguments != null) {
+            String classArg = arguments.getString(ARGUMENT_TEST_CLASS);
+            singleTest = classArg != null && classArg.contains("#"); 
+        }
+        
+        super.onCreate(arguments);
+    }
+
+    protected AndroidTestRunner getAndroidTestRunner() {
+        AndroidTestRunner runner = super.getAndroidTestRunner();
+
+        runner.addTestListener(new TestListener() {
+            private Class<?> lastClass;
+            
+            public void startTest(Test test) {
+                if (test.getClass() != lastClass) {
+                    printMemory(test.getClass());
+                }
+                
+                Thread.currentThread().setContextClassLoader(
+                        test.getClass().getClassLoader());
+            }
+            
+            public void endTest(Test test) {
+                if (test instanceof TestCase) {
+                    if (lastClass == null) {
+                        lastClass = test.getClass();
+                    } else {
+                        if (test.getClass() != lastClass) {
+                            cleanup(lastClass);
+                            lastClass = test.getClass();
+                        }
+                    }
+                }
+            }
+            
+            public void addError(Test test, Throwable t) {
+            }
+            
+            public void addFailure(Test test, AssertionFailedError t) {
+            }
+            
+            /**
+             * Dumps some memory info.
+             */
+            private void printMemory(Class<? extends Test> testClass) {
+                Runtime runtime = Runtime.getRuntime();
+
+                long total = runtime.totalMemory();
+                long free = runtime.freeMemory();
+                long used = total - free;
+                
+                Log.d(TAG, "Total memory  : " + total);
+                Log.d(TAG, "Used memory   : " + used);
+                Log.d(TAG, "Free memory   : " + free);
+                Log.d(TAG, "Now executing : " + testClass.getName());
+            }
+
+            /**
+             * Nulls all static reference fields in the given test class. This
+             * method helps us with those test classes that don't have an
+             * explicit tearDown() method. Normally the garbage collector should
+             * take care of everything, but since JUnit keeps references to all
+             * test cases, a little help might be a good idea.
+             */
+            private void cleanup(Class<?> clazz) {
+                if (clazz != TestCase.class) {
+                    Field[] fields = clazz.getDeclaredFields();
+                    for (int i = 0; i < fields.length; i++) {
+                        Field f = fields[i];
+                        if (!f.getType().isPrimitive() &&
+                                Modifier.isStatic(f.getModifiers())) {
+                            try {
+                                f.setAccessible(true);
+                                f.set(null, null);
+                            } catch (Exception ignored) {
+                                // Nothing we can do about it.
+                            }
+                        }
+                    }
+                    
+                    // don't cleanup the superclass for now
+                    //cleanup(clazz.getSuperclass());
+                }
+            }
+            
+        });
+        
+        return runner;
+    }    
+
+    @Override
+    List<Predicate<TestMethod>> getBuilderRequirements() {
+        List<Predicate<TestMethod>> builderRequirements =
+                super.getBuilderRequirements();
+        Predicate<TestMethod> brokenTestPredicate =
+                Predicates.not(new HasAnnotation(BrokenTest.class));
+        builderRequirements.add(brokenTestPredicate);
+        if (!singleTest) {
+            Predicate<TestMethod> sideEffectPredicate =
+                    Predicates.not(new HasAnnotation(SideEffect.class));
+            builderRequirements.add(sideEffectPredicate);
+        }
+        return builderRequirements;
     }
 }
diff --git a/test-runner/android/test/InstrumentationTestRunner.java b/test-runner/android/test/InstrumentationTestRunner.java
index 044f555..d5e64596 100644
--- a/test-runner/android/test/InstrumentationTestRunner.java
+++ b/test-runner/android/test/InstrumentationTestRunner.java
@@ -43,6 +43,8 @@
 import java.io.PrintStream;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.List;
 
 
 /**
@@ -315,6 +317,8 @@
         } else {
             parseTestClasses(testClassesArg, testSuiteBuilder);
         }
+        
+        testSuiteBuilder.addRequirements(getBuilderRequirements());
 
         mTestRunner = getAndroidTestRunner();
         mTestRunner.setContext(getTargetContext());
@@ -331,6 +335,10 @@
         start();
     }
 
+    List<Predicate<TestMethod>> getBuilderRequirements() {
+        return new ArrayList<Predicate<TestMethod>>();
+    }
+
     /**
      * Parses and loads the specified set of test classes 
      * @param testClassArg - comma-separated list of test classes and methods