diff --git a/toolkit/mozapps/extensions/AddonManager.jsm b/toolkit/mozapps/extensions/AddonManager.jsm
index b55882ee1978..937cd8d88425 100644
--- a/toolkit/mozapps/extensions/AddonManager.jsm
+++ b/toolkit/mozapps/extensions/AddonManager.jsm
@@ -811,6 +811,7 @@ var AddonManager = {
   PENDING_UNINSTALL: 4,
   // Indicates that the Addon will be installed after the application restarts.
   PENDING_INSTALL: 8,
+  PENDING_UPGRADE: 16,
 
   // Constants for permissions in Addon.permissions.
   // Indicates that the Addon can be uninstalled.
diff --git a/toolkit/mozapps/extensions/XPIProvider.jsm b/toolkit/mozapps/extensions/XPIProvider.jsm
index d276c5867082..649c76688545 100644
--- a/toolkit/mozapps/extensions/XPIProvider.jsm
+++ b/toolkit/mozapps/extensions/XPIProvider.jsm
@@ -3610,6 +3610,10 @@ AddonInstall.prototype = {
 
         LOG("Install of " + this.sourceURL.spec + " completed.");
         this.state = AddonManager.STATE_INSTALLED;
+        if (isUpgrade) {
+          delete this.existingAddon.pendingUpgrade;
+          this.existingAddon.pendingUpgrade = this.addon;
+        }
         AddonManagerPrivate.callInstallListeners("onInstallEnded",
                                                  this.listeners, this.wrapper,
                                                  createWrapper(this.addon));
@@ -3978,6 +3982,19 @@ function DBAddonInternal() {
     delete this.defaultLocale;
     return this.defaultLocale = XPIDatabase._getDefaultLocale(this);
   });
+
+  this.__defineGetter__("pendingUpgrade", function() {
+    delete this.pendingUpgrade;
+    for (let i = 0; i < XPIProvider.installs.length; i++) {
+      let install = XPIProvider.installs[i];
+      if (install.state == AddonManager.STATE_INSTALLED &&
+          !(install.addon instanceof DBAddonInternal) &&
+          install.addon.id == this.id &&
+          install.installLocation == this._installLocation) {
+        return this.pendingUpgrade = install.addon;
+      }
+    };
+  });
 }
 
 DBAddonInternal.prototype = {
@@ -4055,6 +4072,10 @@ function AddonWrapper(addon) {
     addon.updateAutomatically = val;
   });
 
+  this.__defineGetter__("pendingUpgrade", function() {
+    return createWrapper(addon.pendingUpgrade);
+  });
+
   this.__defineGetter__("pendingOperations", function() {
     let pending = 0;
     if (!(addon instanceof DBAddonInternal))
@@ -4067,6 +4088,9 @@ function AddonWrapper(addon) {
     else if (!addon.active && (!addon.userDisabled && !addon.appDisabled))
       pending |= AddonManager.PENDING_ENABLE;
 
+    if (addon.pendingUpgrade)
+      pending |= AddonManager.PENDING_UPGRADE;
+
     return pending;
   });
 
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_install.js b/toolkit/mozapps/extensions/test/xpcshell/test_install.js
index 794ea1d5321a..75d0f3b4ed2b 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_install.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_install.js
@@ -282,28 +282,34 @@ function check_test_5() {
   ensure_test_completed();
   AddonManager.getAddon("addon2@tests.mozilla.org", function(olda2) {
     do_check_neq(olda2, null);
-    restartManager();
+    do_check_true(hasFlag(olda2.pendingOperations, AddonManager.PENDING_UPGRADE));
 
     AddonManager.getInstalls(null, function(installs) {
-      do_check_eq(installs, 0);
+      do_check_eq(installs.length, 1);
+      do_check_eq(installs[0].addon, olda2.pendingUpgrade);
+      restartManager();
 
-      AddonManager.getAddon("addon2@tests.mozilla.org", function(a2) {
-        do_check_neq(a2, null);
-        do_check_eq(a2.type, "extension");
-        do_check_eq(a2.version, "3.0");
-        do_check_eq(a2.name, "Real Test 3");
-        do_check_true(a2.isActive);
-        do_check_true(isExtensionInAddonsList(profileDir, a2.id));
-        do_check_true(do_get_addon("test_install2_2").exists());
+      AddonManager.getInstalls(null, function(installs) {
+        do_check_eq(installs.length, 0);
 
-        do_check_eq(a2.installDate.getTime(), gInstallDate);
-        // Update date should be later (or the same if this test is too fast)
-        do_check_true(a2.installDate <= a2.updateDate);
+        AddonManager.getAddon("addon2@tests.mozilla.org", function(a2) {
+          do_check_neq(a2, null);
+          do_check_eq(a2.type, "extension");
+          do_check_eq(a2.version, "3.0");
+          do_check_eq(a2.name, "Real Test 3");
+          do_check_true(a2.isActive);
+          do_check_true(isExtensionInAddonsList(profileDir, a2.id));
+          do_check_true(do_get_addon("test_install2_2").exists());
 
-        a2.uninstall();
-        restartManager(0);
+          do_check_eq(a2.installDate.getTime(), gInstallDate);
+          // Update date should be later (or the same if this test is too fast)
+          do_check_true(a2.installDate <= a2.updateDate);
 
-        run_test_6();
+          a2.uninstall();
+          restartManager(0);
+
+          run_test_6();
+        });
       });
     });
   });