diff --git a/core/src/main/java/hudson/PluginManager.java b/core/src/main/java/hudson/PluginManager.java
index b07123e55e53601878fbb8e65d9e17175558d93f..3a05b02d48ad23aa441a1fb34fbfb2a138f98501 100644
--- a/core/src/main/java/hudson/PluginManager.java
+++ b/core/src/main/java/hudson/PluginManager.java
@@ -1,8 +1,6 @@
 package hudson;
 
-import hudson.model.Hudson;
-import hudson.model.UpdateCenter;
-import hudson.model.AbstractModelObject;
+import hudson.model.*;
 import hudson.util.Service;
 
 import java.util.Enumeration;
@@ -22,6 +20,9 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.apache.commons.logging.LogFactory;
+import org.apache.commons.fileupload.servlet.ServletFileUpload;
+import org.apache.commons.fileupload.disk.DiskFileItemFactory;
+import org.apache.commons.fileupload.FileItem;
 import org.kohsuke.stapler.StaplerRequest;
 import org.kohsuke.stapler.StaplerResponse;
 import org.kohsuke.stapler.QueryParameter;
@@ -60,6 +61,13 @@ public final class PluginManager extends AbstractModelObject {
     // and load plugin-contributed classes.
     public final ClassLoader uberClassLoader = new UberClassLoader();
 
+    /**
+     * Once plugin is uploaded, this flag becomes true.
+     * This is used to report a message that Hudson needs to be restarted
+     * for new plugins to take effect.
+     */
+    public transient volatile boolean pluginUploaded =false;
+
     public PluginManager(ServletContext context) {
         this.context = context;
         rootDir = new File(Hudson.getInstance().getRootDir(),"plugins");
@@ -100,6 +108,13 @@ public final class PluginManager extends AbstractModelObject {
             }
     }
 
+    /**
+     * Retrurns true if any new plugin was added, which means a restart is required for the change to take effect.
+     */
+    public boolean isPluginUploaded() {
+        return pluginUploaded;
+    }
+    
     public List<PluginWrapper> getPlugins() {
         return plugins;
     }
@@ -184,6 +199,35 @@ public final class PluginManager extends AbstractModelObject {
         else        System.setProperty(key,value);
     }
 
+    /**
+     * Uploads a plugin.
+     */
+    public void doUploadPlugin( StaplerRequest req, StaplerResponse rsp ) throws IOException, ServletException {
+        try {
+            Hudson.getInstance().checkPermission(Hudson.ADMINISTER);
+
+            ServletFileUpload upload = new ServletFileUpload(new DiskFileItemFactory());
+
+            // Parse the request
+            FileItem fileItem = (FileItem) upload.parseRequest(req).get(0);
+            String fileName = Util.getFileName(fileItem.getName());
+            if(!fileName.endsWith(".hpi")) {
+                sendError(hudson.model.Messages.Hudson_NotAPlugin(fileName),req,rsp);
+                return;
+            }
+            fileItem.write(new File(rootDir, fileName));
+            fileItem.delete();
+
+            pluginUploaded=true;
+
+            rsp.sendRedirect2(".");
+        } catch (IOException e) {
+            throw e;
+        } catch (Exception e) {// grrr. fileItem.write throws this
+            throw new ServletException(e);
+        }
+    }
+
     private final class UberClassLoader extends ClassLoader {
         public UberClassLoader() {
             super(PluginManager.class.getClassLoader());
diff --git a/core/src/main/java/hudson/model/Hudson.java b/core/src/main/java/hudson/model/Hudson.java
index 6e1756fdcb0139f390efdab23d415b329cb6ba2c..95b815ad6cadc7b1a77273fdc71625cc3fb0d3fa 100644
--- a/core/src/main/java/hudson/model/Hudson.java
+++ b/core/src/main/java/hudson/model/Hudson.java
@@ -272,13 +272,6 @@ public final class Hudson extends View implements ItemGroup<TopLevelItem>, Node,
      */
     private int slaveAgentPort =0;
 
-    /**
-     * Once plugin is uploaded, this flag becomes true.
-     * This is used to report a message that Hudson needs to be restarted
-     * for new plugins to take effect.
-     */
-    private transient boolean pluginUploaded =false;
-
     /**
      * All labels known to Hudson. This allows us to reuse the same label instances
      * as much as possible, even though that's not a strict requirement.
@@ -1899,39 +1892,6 @@ public final class Hudson extends View implements ItemGroup<TopLevelItem>, Node,
         }.start();
     }
 
-    public boolean isPluginUploaded() {
-        return pluginUploaded;
-    }
-
-    /**
-     * Uploads a plugin.
-     */
-    public void doUploadPlugin( StaplerRequest req, StaplerResponse rsp ) throws IOException, ServletException {
-        try {
-            checkPermission(ADMINISTER);
-
-            ServletFileUpload upload = new ServletFileUpload(new DiskFileItemFactory());
-
-            // Parse the request
-            FileItem fileItem = (FileItem) upload.parseRequest(req).get(0);
-            String fileName = Util.getFileName(fileItem.getName());
-            if(!fileName.endsWith(".hpi")) {
-                sendError(Messages.Hudson_NotAPlugin(fileName),req,rsp);
-                return;
-            }
-            fileItem.write(new File(getPluginManager().rootDir, fileName));
-            fileItem.delete();
-
-            pluginUploaded=true;
-
-            rsp.sendRedirect2("managePlugins");
-        } catch (IOException e) {
-            throw e;
-        } catch (Exception e) {// grrr. fileItem.write throws this
-            throw new ServletException(e);
-        }
-    }
-
     /**
      * Do a finger-print check.
      */
diff --git a/core/src/main/java/hudson/model/UpdateCenter.java b/core/src/main/java/hudson/model/UpdateCenter.java
index a26fad32ee9c43249a8feec1838665f3829962d2..3e5a27d5ba29fb4271c181aafa7d783a71e9909b 100644
--- a/core/src/main/java/hudson/model/UpdateCenter.java
+++ b/core/src/main/java/hudson/model/UpdateCenter.java
@@ -405,7 +405,8 @@ public class UpdateCenter implements ModelObject {
                 byte[] buf = new byte[8192];
                 int len;
 
-                File baseDir = Hudson.getInstance().getPluginManager().rootDir;
+                PluginManager pm = Hudson.getInstance().getPluginManager();
+                File baseDir = pm.rootDir;
                 File target = new File(baseDir, plugin.name + ".tmp");
                 OutputStream out = new FileOutputStream(target);
 
@@ -425,6 +426,7 @@ public class UpdateCenter implements ModelObject {
                 }
 
                 LOGGER.info("Installation successful: "+plugin.name);
+                pm.pluginUploaded = true;
                 status = new Success();
             } catch (IOException e) {
                 LOGGER.log(Level.SEVERE, "Failed to install "+plugin.name,e);
diff --git a/core/src/main/resources/hudson/PluginManager/installed.jelly b/core/src/main/resources/hudson/PluginManager/installed.jelly
index a1d878cc4d71a995c3b12ebabb4d44f2a626e0c5..58b3bead90d43cb5e2f98f5090781480648c083f 100644
--- a/core/src/main/resources/hudson/PluginManager/installed.jelly
+++ b/core/src/main/resources/hudson/PluginManager/installed.jelly
@@ -57,7 +57,7 @@
         </j:choose>
       </local:tabBar>
 
-      <j:if test="${app.isPluginUploaded()}">
+      <j:if test="${it.isPluginUploaded()}">
         <div style="margin: 1em; height: 1em">
           <div class="error">
             ${%New plugins will take effect once you restart Hudson}
diff --git a/core/src/main/resources/hudson/model/Hudson/managePlugins.jelly b/core/src/main/resources/hudson/model/Hudson/managePlugins.jelly
index 15bd577ef6d19b01fd1d8e1aef5273d07166d3ba..b541d8c5ef804ba686b2614f60246238fe84bcd1 100644
--- a/core/src/main/resources/hudson/model/Hudson/managePlugins.jelly
+++ b/core/src/main/resources/hudson/model/Hudson/managePlugins.jelly
@@ -10,7 +10,7 @@
     <s:form method="post" action="configSubmit">
       <s:block>
         <h1>${%Installed Plugins}</h1>
-        <j:if test="${app.isPluginUploaded()}">
+        <j:if test="${app.pluginManager.isPluginUploaded()}">
           <div style="margin: 1em; height: 1em">
             <div class="error">
               ${%New plugins will take effect once you restart Hudson}