diff --git a/core/main.mk b/core/main.mk
index bee8c7b..fb1a58f 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -85,6 +85,44 @@
 $(error Directory names containing spaces not supported)
 endif
 
+
+# The windows build server currently uses 1.6.  This will be fixed.
+ifneq ($(HOST_OS),windows)
+
+# Check for the correct version of java
+java_version := $(shell java -version 2>&1 | head -n 1 | grep '[ "]1\.5[\. "$$]')
+ifeq ($(strip $(java_version)),)
+$(info ************************************************************)
+$(info You are attempting to build with the incorrect version)
+$(info of java.)
+$(info $(space))
+$(info Your version is: $(shell java -version 2>&1 | head -n 1).)
+$(info The correct version is: 1.5.)
+$(info $(space))
+$(info Please follow the machine setup instructions at)
+$(info $(space)$(space)$(space)$(space)http://source.android.com/download)
+$(info ************************************************************)
+$(error stop)
+endif
+
+# Check for the correct version of javac
+javac_version := $(shell javac -version 2>&1 | head -n 1 | grep '[ "]1\.5[\. "$$]')
+ifeq ($(strip $(javac_version)),)
+$(info ************************************************************)
+$(info You are attempting to build with the incorrect version)
+$(info of javac.)
+$(info $(space))
+$(info Your version is: $(shell javac -version 2>&1 | head -n 1).)
+$(info The correct version is: 1.5.)
+$(info $(space))
+$(info Please follow the machine setup instructions at)
+$(info $(space)$(space)$(space)$(space)http://source.android.com/download)
+$(info ************************************************************)
+$(error stop)
+endif
+
+endif # windows
+
 # These are the modifier targets that don't do anything themselves, but
 # change the behavior of the build.
 # (must be defined before including definitions.make)
diff --git a/core/tasks/cts.mk b/core/tasks/cts.mk
index 33cdf93..eed9beb 100644
--- a/core/tasks/cts.mk
+++ b/core/tasks/cts.mk
@@ -25,6 +25,8 @@
 endif
 CTS_HOST_JAR := $(HOST_OUT_JAVA_LIBRARIES)/cts.jar
 
+junit_host_jar := $(HOST_OUT_JAVA_LIBRARIES)/junit.jar
+
 CTS_CORE_CASE_LIST := android.core.tests.annotation \
 	android.core.tests.archive \
 	android.core.tests.concurrent \
@@ -76,7 +78,9 @@
 
 DEFAULT_TEST_PLAN := $(PRIVATE_DIR)/resource/plans
 
-$(cts_dir)/all_cts_files_stamp: $(CTS_CASE_LIST) | $(ACP)
+$(cts_dir)/all_cts_files_stamp: PRIVATE_JUNIT_HOST_JAR := $(junit_host_jar)
+
+$(cts_dir)/all_cts_files_stamp: $(CTS_CASE_LIST) $(junit_host_jar) $(ACP)
 # Make necessary directory for CTS
 	@rm -rf $(PRIVATE_CTS_DIR)
 	@mkdir -p $(TMP_DIR)
@@ -87,6 +91,8 @@
 # Copy executable to CTS directory
 	$(hide) $(ACP) -fp $(CTS_HOST_JAR) $(PRIVATE_DIR)/tools
 	$(hide) $(ACP) -fp $(CTS_EXECUTABLE_PATH) $(PRIVATE_DIR)/tools
+# Copy junit jar
+	$(hide) $(ACP) -fp $(PRIVATE_JUNIT_HOST_JAR) $(PRIVATE_DIR)/tools
 # Change mode of the executables
 	$(hide) chmod ug+rwX $(PRIVATE_DIR)/tools/$(notdir $(CTS_EXECUTABLE_PATH))
 	$(foreach apk,$(CTS_CASE_LIST), \
diff --git a/tools/dexpreopt/afar/Android.mk b/tools/dexpreopt/afar/Android.mk
index d224675..9f1b987 100644
--- a/tools/dexpreopt/afar/Android.mk
+++ b/tools/dexpreopt/afar/Android.mk
@@ -24,6 +24,6 @@
 LOCAL_SHARED_LIBRARIES := libz
 
 LOCAL_MODULE := afar
-LOCAL_MODULE_TAGS := tests
+LOCAL_MODULE_TAGS := optional
 
 include $(BUILD_EXECUTABLE)
diff --git a/tools/dexpreopt/dexopt-wrapper/Android.mk b/tools/dexpreopt/dexopt-wrapper/Android.mk
index e6ca389..ae2b6a3 100644
--- a/tools/dexpreopt/dexopt-wrapper/Android.mk
+++ b/tools/dexpreopt/dexopt-wrapper/Android.mk
@@ -31,6 +31,6 @@
 
 LOCAL_MODULE := dexopt-wrapper
 
-LOCAL_MODULE_TAGS := tests
+LOCAL_MODULE_TAGS := optional
 
 include $(BUILD_EXECUTABLE)
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index afb61a3..a07ff7c 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -63,18 +63,29 @@
 def BuildAndAddBootableImage(sourcedir, targetname, output_zip):
   """Take a kernel, cmdline, and ramdisk directory from the input (in
   'sourcedir'), and turn them into a boot image.  Put the boot image
-  into the output zip file under the name 'targetname'."""
+  into the output zip file under the name 'targetname'.  Returns
+  targetname on success or None on failure (if sourcedir does not
+  appear to contain files for the requested image)."""
 
   print "creating %s..." % (targetname,)
 
   img = BuildBootableImage(sourcedir)
+  if img is None:
+    return None
 
   CheckSize(img, targetname)
   ZipWriteStr(output_zip, targetname, img)
+  return targetname
 
 def BuildBootableImage(sourcedir):
   """Take a kernel, cmdline, and ramdisk directory from the input (in
-  'sourcedir'), and turn them into a boot image.  Return the image data."""
+  'sourcedir'), and turn them into a boot image.  Return the image
+  data, or None if sourcedir does not appear to contains files for
+  building the requested image."""
+
+  if (not os.access(os.path.join(sourcedir, "RAMDISK"), os.F_OK) or
+      not os.access(os.path.join(sourcedir, "kernel"), os.F_OK)):
+    return None
 
   ramdisk_img = tempfile.NamedTemporaryFile()
   img = tempfile.NamedTemporaryFile()
@@ -89,15 +100,25 @@
   assert p1.returncode == 0, "mkbootfs of %s ramdisk failed" % (targetname,)
   assert p2.returncode == 0, "minigzip of %s ramdisk failed" % (targetname,)
 
-  cmdline = open(os.path.join(sourcedir, "cmdline")).read().rstrip("\n")
-  p = Run(["mkbootimg",
-           "--kernel", os.path.join(sourcedir, "kernel"),
-           "--cmdline", cmdline,
-           "--ramdisk", ramdisk_img.name,
-           "--output", img.name],
-          stdout=subprocess.PIPE)
+  cmd = ["mkbootimg", "--kernel", os.path.join(sourcedir, "kernel")]
+
+  fn = os.path.join(sourcedir, "cmdline")
+  if os.access(fn, os.F_OK):
+    cmd.append("--cmdline")
+    cmd.append(open(fn).read().rstrip("\n"))
+
+  fn = os.path.join(sourcedir, "base")
+  if os.access(fn, os.F_OK):
+    cmd.append("--base")
+    cmd.append(open(fn).read().rstrip("\n"))
+
+  cmd.extend(["--ramdisk", ramdisk_img.name,
+              "--output", img.name])
+
+  p = Run(cmd, stdout=subprocess.PIPE)
   p.communicate()
-  assert p.returncode == 0, "mkbootimg of %s image failed" % (targetname,)
+  assert p.returncode == 0, "mkbootimg of %s image failed" % (
+      os.path.basename(sourcedir),)
 
   img.seek(os.SEEK_SET, 0)
   data = img.read()
diff --git a/tools/releasetools/ota_from_target_files b/tools/releasetools/ota_from_target_files
index 1a6ebbf..ea4c752 100755
--- a/tools/releasetools/ota_from_target_files
+++ b/tools/releasetools/ota_from_target_files
@@ -288,11 +288,9 @@
 
   info = input_zip.read("OTA/android-info.txt")
   m = re.search(r"require\s+version-bootloader\s*=\s*(\S+)", info)
-  if not m:
-    raise ExternalError("failed to find required bootloaders in "
-                        "android-info.txt")
-  bootloaders = m.group(1).split("|")
-  script.AssertSomeBootloader(*bootloaders)
+  if m:
+    bootloaders = m.group(1).split("|")
+    script.AssertSomeBootloader(*bootloaders)
 
 
 def WriteFullOTAPackage(input_zip, output_zip):
@@ -312,8 +310,12 @@
 
   script.ShowProgress(0.1, 0)
 
-  common.ZipWriteStr(output_zip, "radio.img", input_zip.read("RADIO/image"))
-  script.WriteFirmwareImage("radio", "radio.img")
+  try:
+    common.ZipWriteStr(output_zip, "radio.img", input_zip.read("RADIO/image"))
+    script.WriteFirmwareImage("radio", "radio.img")
+  except KeyError:
+    print "warning: no radio image in input target_files; not flashing radio"
+
   script.ShowProgress(0.5, 0)
 
   if OPTIONS.wipe_user_data:
@@ -326,9 +328,10 @@
   symlinks = CopySystemFiles(input_zip, output_zip)
   script.MakeSymlinks(symlinks)
 
-  common.BuildAndAddBootableImage(os.path.join(OPTIONS.input_tmp, "RECOVERY"),
-                                  "system/recovery.img", output_zip)
-  Item.Get("system/recovery.img", dir=False)
+  if common.BuildAndAddBootableImage(
+      os.path.join(OPTIONS.input_tmp, "RECOVERY"),
+      "system/recovery.img", output_zip):
+    Item.Get("system/recovery.img", dir=False)
 
   FixPermissions(script)
 
@@ -415,7 +418,7 @@
     return bp
   m = re.search(re.escape(property) + r"=(.*)\n", bp)
   if not m:
-    raise ExternalException("couldn't find %s in build.prop" % (property,))
+    raise common.ExternalError("couldn't find %s in build.prop" % (property,))
   return m.group(1).strip()
 
 
@@ -467,7 +470,7 @@
     if sf is None or fn in OPTIONS.require_verbatim:
       # This file should be included verbatim
       if fn in OPTIONS.prohibit_verbatim:
-        raise ExternalError("\"%s\" must be sent verbatim" % (fn,))
+        raise common.ExternalError("\"%s\" must be sent verbatim" % (fn,))
       print "send", fn, "verbatim"
       tf.AddToZip(output_zip)
       verbatim_targets.append((fn, tf.size))
@@ -577,7 +580,9 @@
     script.FormatPartition("userdata")
 
   script.Print("Removing unneeded files...")
-  script.DeleteFiles(["/"+i[0] for i in verbatim_targets])
+  script.DeleteFiles(["/"+i[0] for i in verbatim_targets] +
+                     ["/"+i for i in sorted(source_data)
+                            if i not in target_data])
 
   if updating_boot:
     # Produce the boot image by applying a patch to the current