diff --git a/core/src/main/java/hudson/PluginManager.java b/core/src/main/java/hudson/PluginManager.java
index 2fa391e6b1..d4cbe81e6f 100644
--- a/core/src/main/java/hudson/PluginManager.java
+++ b/core/src/main/java/hudson/PluginManager.java
@@ -364,7 +364,7 @@ public final class PluginManager extends AbstractModelObject {
                 UpdateCenter.Plugin p = Hudson.getInstance().getUpdateCenter().getPlugin(n);
                 if(p==null)
                     throw new Failure("No such plugin: "+n);
-                p.install();
+                p.deploy();
             }
         }
         rsp.sendRedirect("../updateCenter/");
diff --git a/core/src/main/java/hudson/cli/GroovyCommand.java b/core/src/main/java/hudson/cli/GroovyCommand.java
index 32c05da645..8607a3b4bc 100644
--- a/core/src/main/java/hudson/cli/GroovyCommand.java
+++ b/core/src/main/java/hudson/cli/GroovyCommand.java
@@ -81,7 +81,7 @@ public class GroovyCommand extends CLICommand implements Serializable {
      */
     private String loadScript() throws CmdLineException, IOException, InterruptedException {
         if(script==null)
-            throw new CmdLineException("No script is specified");
+            throw new CmdLineException(null, "No script is specified");
         return channel.call(new Callable<String,IOException>() {
             public String call() throws IOException {
                 if(script.equals("="))
diff --git a/core/src/main/java/hudson/cli/handlers/AbstractProjectOptionHandler.java b/core/src/main/java/hudson/cli/handlers/AbstractProjectOptionHandler.java
index f3bde0fb13..e332862a79 100644
--- a/core/src/main/java/hudson/cli/handlers/AbstractProjectOptionHandler.java
+++ b/core/src/main/java/hudson/cli/handlers/AbstractProjectOptionHandler.java
@@ -51,7 +51,7 @@ public class AbstractProjectOptionHandler extends OptionHandler<AbstractProject>
 
         AbstractProject s = h.getItemByFullName(src,AbstractProject.class);
         if (s==null)
-            throw new CmdLineException("No such job '"+src+"' perhaps you meant "+ AbstractProject.findNearest(src)+"?");
+            throw new CmdLineException(owner, "No such job '"+src+"' perhaps you meant "+ AbstractProject.findNearest(src)+"?");
         setter.addValue(s);
         return 1;
     }
diff --git a/core/src/main/java/hudson/cli/handlers/TopLevelItemOptionHandler.java b/core/src/main/java/hudson/cli/handlers/TopLevelItemOptionHandler.java
index 9206816e87..2bfbe58199 100644
--- a/core/src/main/java/hudson/cli/handlers/TopLevelItemOptionHandler.java
+++ b/core/src/main/java/hudson/cli/handlers/TopLevelItemOptionHandler.java
@@ -29,7 +29,7 @@ public class TopLevelItemOptionHandler extends OptionHandler<TopLevelItem> {
 
         TopLevelItem s = h.getItem(src);
         if (s==null)
-            throw new CmdLineException("No such job '"+src+"' perhaps you meant "+ AbstractProject.findNearest(src)+"?");
+            throw new CmdLineException(owner, "No such job '"+src+"' perhaps you meant "+ AbstractProject.findNearest(src)+"?");
         setter.addValue(s);
         return 1;
     }
diff --git a/core/src/main/java/hudson/diagnosis/HudsonHomeDiskUsageMonitor.java b/core/src/main/java/hudson/diagnosis/HudsonHomeDiskUsageMonitor.java
index 1e8ae0c4e4..ae1f5ea1b1 100644
--- a/core/src/main/java/hudson/diagnosis/HudsonHomeDiskUsageMonitor.java
+++ b/core/src/main/java/hudson/diagnosis/HudsonHomeDiskUsageMonitor.java
@@ -30,7 +30,7 @@ import hudson.Extension;
 import hudson.ExtensionPoint;
 import hudson.ExtensionList;
 import org.kohsuke.stapler.HttpResponse;
-import org.kohsuke.stapler.HttpRedirect;
+import org.kohsuke.stapler.HttpResponses;
 import org.kohsuke.stapler.QueryParameter;
 
 import java.io.IOException;
@@ -62,9 +62,9 @@ public final class HudsonHomeDiskUsageMonitor extends AdministrativeMonitor {
     public HttpResponse doAct(@QueryParameter String no) throws IOException {
         if(no!=null) {
             disable(true);
-            return HttpRedirect.fromContextPath("/manage");
+            return HttpResponses.redirectViaContextPath("/manage");
         } else {
-            return new HttpRedirect(".");
+            return HttpResponses.redirectToDot();
         }
     }
 
diff --git a/core/src/main/java/hudson/model/BuildAuthorizationToken.java b/core/src/main/java/hudson/model/BuildAuthorizationToken.java
index ef8f05ef4a..2af173ca7e 100644
--- a/core/src/main/java/hudson/model/BuildAuthorizationToken.java
+++ b/core/src/main/java/hudson/model/BuildAuthorizationToken.java
@@ -23,7 +23,7 @@
  */
 package hudson.model;
 
-import com.thoughtworks.xstream.converters.basic.AbstractBasicConverter;
+import com.thoughtworks.xstream.converters.basic.AbstractSingleValueConverter;
 import hudson.Util;
 import hudson.security.ACL;
 import org.kohsuke.stapler.StaplerRequest;
@@ -75,17 +75,17 @@ public final class BuildAuthorizationToken {
         return token;
     }
 
-    public static final class ConverterImpl extends AbstractBasicConverter {
+    public static final class ConverterImpl extends AbstractSingleValueConverter {
         public boolean canConvert(Class type) {
             return type== BuildAuthorizationToken.class;
         }
 
-        protected Object fromString(String str) {
+        public Object fromString(String str) {
             return new BuildAuthorizationToken(str);
         }
 
         @Override
-        protected String toString(Object obj) {
+        public String toString(Object obj) {
             return ((BuildAuthorizationToken)obj).token;
         }
     }
diff --git a/core/src/main/java/hudson/model/Fingerprint.java b/core/src/main/java/hudson/model/Fingerprint.java
index fe39383eeb..a91498dd5b 100644
--- a/core/src/main/java/hudson/model/Fingerprint.java
+++ b/core/src/main/java/hudson/model/Fingerprint.java
@@ -760,7 +760,7 @@ public class Fingerprint implements ModelObject, Saveable {
         XSTREAM.alias("ranges",RangeSet.class);
         XSTREAM.registerConverter(new HexBinaryConverter(),10);
         XSTREAM.registerConverter(new RangeSet.ConverterImpl(
-            new CollectionConverter(XSTREAM.getClassMapper()) {
+            new CollectionConverter(XSTREAM.getMapper()) {
                 @Override
                 protected Object createCollection(Class type) {
                     return new ArrayList();
diff --git a/core/src/main/java/hudson/model/Hudson.java b/core/src/main/java/hudson/model/Hudson.java
index 386e224fdc..5dd6dd42ba 100644
--- a/core/src/main/java/hudson/model/Hudson.java
+++ b/core/src/main/java/hudson/model/Hudson.java
@@ -1511,6 +1511,7 @@ public final class Hudson extends Node implements ItemGroup<TopLevelItem>, Stapl
         return "";
     }
 
+    @Override
     public String getSearchUrl() {
         return "";
     }
@@ -2118,7 +2119,7 @@ public final class Hudson extends Node implements ItemGroup<TopLevelItem>, Stapl
         for( Computer c : computers.values() ) {
             c.interrupt();
             c.kill();
-            pending.add(c.disconnect());
+            pending.add(c.disconnect(null));
         }
         if(udpBroadcastThread!=null)
             udpBroadcastThread.shutdown();
diff --git a/core/src/main/java/hudson/model/Job.java b/core/src/main/java/hudson/model/Job.java
index 9424b9fed3..ff989a6531 100644
--- a/core/src/main/java/hudson/model/Job.java
+++ b/core/src/main/java/hudson/model/Job.java
@@ -602,10 +602,10 @@ public abstract class Job<JobT extends Job<JobT, RunT>, RunT extends Run<JobT, R
             int n = Integer.parseInt(id);
             RunT r = getBuildByNumber(n);
             if (r==null)
-                throw new CmdLineException("No such build '#"+n+"' exists");
+                throw new CmdLineException(null, "No such build '#"+n+"' exists");
             return r;
         } catch (NumberFormatException e) {
-            throw new CmdLineException(id+ "is not a number");
+            throw new CmdLineException(null, id+ "is not a number");
         }
     }
 
diff --git a/core/src/main/java/hudson/model/LoadStatistics.java b/core/src/main/java/hudson/model/LoadStatistics.java
index 0c33ac96ce..6853889270 100644
--- a/core/src/main/java/hudson/model/LoadStatistics.java
+++ b/core/src/main/java/hudson/model/LoadStatistics.java
@@ -211,7 +211,7 @@ public abstract class LoadStatistics {
             }
 
             // update statistics of the entire system
-            ComputerSet cs = h.getComputer();
+            ComputerSet cs = new ComputerSet();
             h.overallLoad.totalExecutors.update(cs.getTotalExecutors());
             h.overallLoad.busyExecutors .update(cs.getBusyExecutors());
             int q=0;
diff --git a/core/src/main/java/hudson/model/OverallLoadStatistics.java b/core/src/main/java/hudson/model/OverallLoadStatistics.java
index 557de5590b..adbfa1ee24 100644
--- a/core/src/main/java/hudson/model/OverallLoadStatistics.java
+++ b/core/src/main/java/hudson/model/OverallLoadStatistics.java
@@ -53,12 +53,12 @@ public class OverallLoadStatistics extends LoadStatistics {
 
     @Override
     public int computeIdleExecutors() {
-        return Hudson.getInstance().getComputer().getIdleExecutors();
+        return new ComputerSet().getIdleExecutors();
     }
 
     @Override
     public int computeTotalExecutors() {
-        return Hudson.getInstance().getComputer().getTotalExecutors();
+        return new ComputerSet().getTotalExecutors();
     }
 
     @Override
diff --git a/core/src/main/java/hudson/model/Result.java b/core/src/main/java/hudson/model/Result.java
index d86fc419bc..2dd00a56d2 100644
--- a/core/src/main/java/hudson/model/Result.java
+++ b/core/src/main/java/hudson/model/Result.java
@@ -23,8 +23,8 @@
  */
 package hudson.model;
 
-import com.thoughtworks.xstream.converters.Converter;
-import com.thoughtworks.xstream.converters.basic.AbstractBasicConverter;
+import com.thoughtworks.xstream.converters.SingleValueConverter;
+import com.thoughtworks.xstream.converters.basic.AbstractSingleValueConverter;
 import org.kohsuke.stapler.export.CustomExportedBean;
 
 import java.io.Serializable;
@@ -132,12 +132,12 @@ public final class Result implements Serializable, CustomExportedBean {
 
     private static final Result[] all = new Result[] {SUCCESS,UNSTABLE,FAILURE,NOT_BUILT,ABORTED};
 
-    public static final Converter conv = new AbstractBasicConverter () {
+    public static final SingleValueConverter conv = new AbstractSingleValueConverter () {
         public boolean canConvert(Class clazz) {
             return clazz==Result.class;
         }
 
-        protected Object fromString(String s) {
+        public Object fromString(String s) {
             return Result.fromString(s);
         }
     };
diff --git a/core/src/main/java/hudson/slaves/ConnectionActivityMonitor.java b/core/src/main/java/hudson/slaves/ConnectionActivityMonitor.java
index 3b545541ac..e797ca4344 100644
--- a/core/src/main/java/hudson/slaves/ConnectionActivityMonitor.java
+++ b/core/src/main/java/hudson/slaves/ConnectionActivityMonitor.java
@@ -66,7 +66,7 @@ public class ConnectionActivityMonitor extends AsyncPeriodicWork {
 
                     if (lastPing!=null && now-lastPing > TIMEOUT) {
                         LOGGER.info("Repeated ping attempts failed on "+c.getName()+". Disconnecting");
-                        c.disconnect(); // TODO: explain the cause
+                        c.disconnect(OfflineCause.create(Messages._ConnectionActivityMonitor_OfflineCause()));
                     } else {
                         // send a ping. if we receive a reply, it will be reflected in the next getLastHeard() call.
                         channel.callAsync(PING_COMMAND);
diff --git a/core/src/main/java/hudson/tasks/CommandInterpreter.java b/core/src/main/java/hudson/tasks/CommandInterpreter.java
index 38a8bc8cbe..c81cbb706b 100644
--- a/core/src/main/java/hudson/tasks/CommandInterpreter.java
+++ b/core/src/main/java/hudson/tasks/CommandInterpreter.java
@@ -53,6 +53,7 @@ public abstract class CommandInterpreter extends Builder {
         return command;
     }
 
+    @Override
     public boolean perform(AbstractBuild<?,?> build, Launcher launcher, BuildListener listener) throws InterruptedException {
         return perform(build,launcher,(TaskListener)listener);
     }
diff --git a/core/src/main/java/hudson/tasks/Shell.java b/core/src/main/java/hudson/tasks/Shell.java
index ed6a8e8a73..66780e5b73 100644
--- a/core/src/main/java/hudson/tasks/Shell.java
+++ b/core/src/main/java/hudson/tasks/Shell.java
@@ -161,7 +161,8 @@ public class Shell extends CommandInterpreter {
             return new Shell(data.getString("shell"));
         }
 
-        public boolean configure( StaplerRequest req ) {
+        @Override
+        public boolean configure(StaplerRequest req, JSONObject data) {
             setShell(req.getParameter("shell"));
             return true;
         }
diff --git a/core/src/main/java/hudson/util/CopyOnWriteList.java b/core/src/main/java/hudson/util/CopyOnWriteList.java
index e230e3e27d..745c86669c 100644
--- a/core/src/main/java/hudson/util/CopyOnWriteList.java
+++ b/core/src/main/java/hudson/util/CopyOnWriteList.java
@@ -23,7 +23,7 @@
  */
 package hudson.util;
 
-import com.thoughtworks.xstream.alias.CannotResolveClassException;
+import com.thoughtworks.xstream.mapper.CannotResolveClassException;
 import com.thoughtworks.xstream.converters.Converter;
 import com.thoughtworks.xstream.converters.MarshallingContext;
 import com.thoughtworks.xstream.converters.UnmarshallingContext;
diff --git a/core/src/main/java/hudson/util/RobustCollectionConverter.java b/core/src/main/java/hudson/util/RobustCollectionConverter.java
index e847559e32..e0efb7e100 100644
--- a/core/src/main/java/hudson/util/RobustCollectionConverter.java
+++ b/core/src/main/java/hudson/util/RobustCollectionConverter.java
@@ -23,7 +23,7 @@
  */
 package hudson.util;
 
-import com.thoughtworks.xstream.alias.CannotResolveClassException;
+import com.thoughtworks.xstream.mapper.CannotResolveClassException;
 import com.thoughtworks.xstream.converters.UnmarshallingContext;
 import com.thoughtworks.xstream.converters.collections.CollectionConverter;
 import com.thoughtworks.xstream.converters.reflection.ReflectionProvider;
diff --git a/core/src/main/java/hudson/util/RobustReflectionConverter.java b/core/src/main/java/hudson/util/RobustReflectionConverter.java
index d5abb3ae6e..f4829c0a17 100644
--- a/core/src/main/java/hudson/util/RobustReflectionConverter.java
+++ b/core/src/main/java/hudson/util/RobustReflectionConverter.java
@@ -96,10 +96,9 @@ public class RobustReflectionConverter implements Converter {
         // Attributes might be preferred to child elements ...
          reflectionProvider.visitSerializableFields(source, new ReflectionProvider.Visitor() {
             public void visit(String fieldName, Class type, Class definedIn, Object value) {
-                SingleValueConverter converter = mapper.getConverterFromItemType(fieldName, type);
-                if (converter == null) {
-                    converter = mapper.getConverterFromItemType(type);
-                }
+                SingleValueConverter converter = mapper.getConverterFromItemType(fieldName, type, definedIn);
+                if (converter == null) converter = mapper.getConverterFromItemType(fieldName, type);
+                if (converter == null) converter = mapper.getConverterFromItemType(type);
                 if (converter != null) {
                     if (value != null) {
                         final String str = converter.toString(value);
diff --git a/core/src/main/resources/hudson/slaves/Messages.properties b/core/src/main/resources/hudson/slaves/Messages.properties
index 5bb0d9ae6e..5aef0430f0 100644
--- a/core/src/main/resources/hudson/slaves/Messages.properties
+++ b/core/src/main/resources/hudson/slaves/Messages.properties
@@ -28,6 +28,7 @@ JNLPLauncher.displayName=Launch slave agents via JNLP
 ComputerLauncher.unexpectedError=Unexpected error in launching a slave. This is probably a bug in Hudson
 ComputerLauncher.abortedLaunch=Launching slave process aborted.
 CommandLauncher.NoLaunchCommand=No launch command specified
+ConnectionActivityMonitor.OfflineCause=Repeated ping attempts failed
 DumbSlave.displayName=Dumb Slave
 NodeProvisioner.EmptyString=
 SimpleScheduledRetentionStrategy.FinishedUpTime=Computer has finished its scheduled uptime