diff --git a/browser/components/privatebrowsing/src/nsPrivateBrowsingService.js b/browser/components/privatebrowsing/src/nsPrivateBrowsingService.js
index e8e7d915a4c..fae7d40d094 100644
--- a/browser/components/privatebrowsing/src/nsPrivateBrowsingService.js
+++ b/browser/components/privatebrowsing/src/nsPrivateBrowsingService.js
@@ -174,6 +174,9 @@ PrivateBrowsingService.prototype = {
             this._savedBrowserState = blankState;
         }
       }
+
+      this._closePageInfoWindows();
+
       if (!this._quitting && this._saveSession) {
         let browserWindow = this._getBrowserWindow();
 
@@ -210,6 +213,8 @@ PrivateBrowsingService.prototype = {
       if (!this._inPrivateBrowsing) {
         ss.setBrowserState(this._savedBrowserState);
         this._savedBrowserState = null;
+
+        this._closePageInfoWindows();
       }
       else {
         // otherwise, if we have transitioned into private browsing mode, load
@@ -252,6 +257,16 @@ PrivateBrowsingService.prototype = {
            getMostRecentWindow("navigator:browser");
   },
 
+  _closePageInfoWindows: function PBS__closePageInfoWindows() {
+    let pageInfoEnum = Cc["@mozilla.org/appshell/window-mediator;1"].
+                       getService(Ci.nsIWindowMediator).
+                       getEnumerator("Browser:page-info");
+    while (pageInfoEnum.hasMoreElements()) {
+      let win = pageInfoEnum.getNext();
+      win.close();
+    }
+  },
+
   // nsIObserver
 
   observe: function PBS_observe(aSubject, aTopic, aData) {
diff --git a/browser/components/privatebrowsing/test/browser/Makefile.in b/browser/components/privatebrowsing/test/browser/Makefile.in
index 927e9179163..f49a4add7ed 100644
--- a/browser/components/privatebrowsing/test/browser/Makefile.in
+++ b/browser/components/privatebrowsing/test/browser/Makefile.in
@@ -58,6 +58,7 @@ _BROWSER_TEST_FILES =  \
 		browser_privatebrowsing_windowtitle_page.html \
 		browser_privatebrowsing_urlbarfocus.js \
 		browser_privatebrowsing_forgetthissite.js \
+		browser_privatebrowsing_pageinfo.js \
 		$(NULL)
 # Test for bug 463256 disabled until we figure why it fails intermittently (bug 486640)
 #		browser_privatebrowsing_sslsite_transition.js \
diff --git a/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_pageinfo.js b/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_pageinfo.js
new file mode 100644
index 00000000000..57f9fc8c502
--- /dev/null
+++ b/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_pageinfo.js
@@ -0,0 +1,119 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Private Browsing Tests.
+ *
+ * The Initial Developer of the Original Code is
+ * Ehsan Akhgari.
+ * Portions created by the Initial Developer are Copyright (C) 2009
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Ehsan Akhgari <ehsan.akhgari@gmail.com> (Original Author)
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+// This test makes sure that the page info dialogs will close when entering or
+// exiting the private browsing mode.
+
+function test() {
+  // initialization
+  let pb = Cc["@mozilla.org/privatebrowsing;1"].
+           getService(Ci.nsIPrivateBrowsingService);
+  let obs = Cc["@mozilla.org/observer-service;1"].
+            getService(Ci.nsIObserverService);
+  let ww = Cc["@mozilla.org/embedcomp/window-watcher;1"].
+           getService(Ci.nsIWindowWatcher);
+
+  function runTest(aPBMode, aCallBack) {
+    const kTestURL1 = "data:text/html,Test Page 1";
+    let tab1 = gBrowser.addTab();
+    gBrowser.selectedTab = tab1;
+    let browser1 = gBrowser.getBrowserForTab(tab1);
+    browser1.addEventListener("load", function() {
+      browser1.removeEventListener("load", arguments.callee, true);
+
+      let pageInfo1 = BrowserPageInfo();
+      obs.addObserver({
+        observe: function (aSubject, aTopic, aData) {
+          obs.removeObserver(this, "page-info-dialog-loaded");
+
+          const kTestURL2 = "data:text/plain,Test Page 2";
+          let tab2 = gBrowser.addTab();
+          gBrowser.selectedTab = tab2;
+          let browser2 = gBrowser.getBrowserForTab(tab2);
+          browser2.addEventListener("load", function () {
+            browser2.removeEventListener("load", arguments.callee, true);
+
+            let pageInfo2 = BrowserPageInfo();
+            obs.addObserver({
+              observe: function (aSubject, aTopic, aData) {
+                obs.removeObserver(this, "page-info-dialog-loaded");
+
+                ww.registerNotification({
+                  observe: function (aSubject, aTopic, aData) {
+                    is(aTopic, "domwindowclosed", "We should only receive window closed notifications");
+                    let win = aSubject.QueryInterface(Ci.nsIDOMWindow);
+                    if (win == pageInfo1) {
+                      ok(true, "Page info 1 being closed as expected");
+                      pageInfo1 = null;
+                    }
+                    else if (win == pageInfo2) {
+                      ok(true, "Page info 2 being closed as expected");
+                      pageInfo2 = null;
+                    }
+                    else
+                      ok(false, "The closed window should be one of the two page info windows");
+
+                    if (!pageInfo1 && !pageInfo2) {
+                      ww.unregisterNotification(this);
+
+                      aCallBack();
+                    }
+                  }
+                });
+
+                pb.privateBrowsingEnabled = aPBMode;
+              }
+            }, "page-info-dialog-loaded", false);
+          }, true);
+          browser2.loadURI(kTestURL2);
+        }
+      }, "page-info-dialog-loaded", false);
+    }, true);
+    browser1.loadURI(kTestURL1);
+  }
+
+  runTest(true, function() {
+    runTest(false, function() {
+      gBrowser.removeCurrentTab();
+      gBrowser.removeCurrentTab();
+
+      finish();
+    });
+  });
+
+  waitForExplicitFinish();
+}